# Africa Hydropower Modernisation

# Programme

## Continent-wide mapping of hydropower rehabilitation

## candidates

### June 2023

* * *

# Africa Hydropower Modernisation

# Programme

**SEFA FUND PARTNERS**

* * *

Contents

Acknowledgements

This Report was written and prepared by the International
Hydropower Association (IHA) and commissioned and funded
by the Sustainable Energy Fund for Africa (SEFA) initiated Africa
Hydropower Modernisation Programme. SEFA is a special fund
managed by the African Development Bank (AfDB).
THE TEAM
AfDB/SEFA
João Cunha, Leopold Ruppert, Stella Mandago, Anders Pedersen,
Matthieu Jalard, Frederica Lourenço
IHA
Alex Campbell, Matteo Bianciotto, Acile Hammoud, Debbie Grey,
Chang Liu, David Samuel, Bill Girling, Rebecca Ellis

Acknowledgements 4
Acronyms 6
Executive summary 8
Report structure 13
PART 01 - GENERAL MODERNISATION BACKGROUND
SECTION 01 Background information 16
SECTION 02 Drivers and opportunities of modernisation 22
SECTION 03 E&S implications associated with modernisation projects 51
SECTION 04 Modernisation cost benchmarking 57
PART 02 - AFRICA - MAPPING OF HYDROPOWER MODERNISATION POTENTIAL
SECTION 05 African context 68
SECTION 06 Methodology 72
SECTION 07 Summary of findings 92
SECTION 08 E&S sustainability review of high need plants 104
SECTION 09 Conclusions and recommendations 108
References 112

* * *

Acronyms

AC

AAR

AFD

DC

AfDB

DRC

EOI

AHMP

ESIA

EAPP

CAPEX

FPV

Alternate current

Agence française de développement

African Development Bank

HESG Hydropower Sustainability Environmental, Social and Governance Gap

Direct current

Eastern Africa Power Pool

Floating photovoltaic

Environmental and sustainability

Democratic Republic of the Congo

Greenhouse gas

Giga watt

HGIIP Hydropower Sustainability Guidelines on Good International Industry Practice

HPP Hydropower plant

HSH Hydro-solar PV hybrid

HVDC High voltage Direct Current line

International Energy Association

IFI International Financial Institution

IHA International Hydropower Association

Independent Power Producer

m3

m

IPP

km2

kW

LCOE

kWh

m2

LEC

TWh

MVA

MW

Levelised cost of electricity

Kilo watt

VRA

Liberia Electricity Corporation

Kilo watt hour

N

Meter

Cubic meter

National Interconnected Transmission System

ONEE

No

Original Equipment Manufacturer

Operation and maintenance

OPEX

PSH

Office National de L'Electricite

Operating expenses

Uganda Electricity Generation Company Ltd.

Pump storage hydropower

Photovoltaic

Volta River Authority

* * *

Executive summary

This high-level screening study,
commissioned by the African Development
Bank (AfDB) through its Sustainable Energy
Fund for Africa (SEFA) funded Africa
Hydropower Modernisation Programme
(AHMP), presents the results of a 12-month
continent-wide mapping of hydropower
facilities eligible for modernisation carried out
by the International Hydropower Association
(IHA).

Regarding energy supply and global
development, Africa is one of the continents
that will face the most difficult challenges
over the coming decades. African countries
will need to progressively increase their
domestic power supply to meet the demand
for power required to develop their economy
and provide electricity for millions of people
to improve their living standards. In doing so,
this energy transition will need to be done
sustainably. Even though Africa currently is
only responsible for 4% of global greenhouse
gas emissions, the worldwide challenge of
mitigating climate change will impose limits
on future emissions. Hydropower can offer
a valuable contribution to ensuring that

In 2019 Africa’s gross generating capacity of
1
all forms of energy was in excess of 245 GW.
Hydropower in Africa currently contributes
to 16% of the total capacity and is today
the most mature and flexible source of
renewable electricity at scale. It accounts
for 80% of the renewable energy generated
2
on the continent. As of 2022, the installed
hydropower capacity was 40 GW, and of
3
these, over 60% is more than 20 years old.

GW). All regions had additional capacity in
medium need, particularly Southern Africa (5
GW) and North Africa (3 GW).

Table 01 shows a regional breakdown of
the modernisation needs identified by the
study. All plants classified in high need of
modernisation were in Sub-Saharan Africa,
and in terms of installed capacity, close to
80% is located across West (2.1 GW) and
Central Africa (1.6 GW), with the remaining
in East (0.6 GW) and Southern Africa (0.3

Table 01 shows a regional breakdown of
the modernisation needs identified by the
study. All plants classified in high need of
modernisation were in Sub-Saharan Africa,
and in terms of installed capacity, close to
80% is located across West (2.1 GW) and
Central Africa (1.6 GW), with the remaining
in East (0.6 GW) and Southern Africa (0.3

Table 01. Regional overview of modernisation needs by number of
stations and installed capacity

| Regions | Low need |  | Medium need |  | High need |  |
| --- | --- | --- | --- | --- | --- | --- |
|  | No. stations | Capacity(MW) | No. stations | Capacity(MW) | No. stations | Capacity(MW) |
| North Africa | 0 | 0 | 7 | 3,094 | 0 | 0 |
| West Africa | 3 | 1,268 | 3 | 430 | 4 | 2,103 |
| East Africa | 6 | 538 | 6 | 938 | 7 | 625 |
| Central Africa | 5 | 923 | 5 | 666 | 3 | 1,557 |
| Southern Africa | 16 | 6,800 | 15 | 4,961 | 7 | 337 |
| TOTALS | 30 | 9,529 | 36 | 10,089 | 21 | 4,621 |

* * *

The study has identified the ageing of the electromechanical
components, lack of access to spare parts and the need for
maintenance on the civil structures as the main trigger for
modernisation projects. Numerous plants classified in the
high-need category are operating with legacy technology,
often at derated capacity, with units operating in a state of
disrepair or entirely out of service.

In order to secure reliable, efficient, and safe electricity
generation from the plants in the high-need category, IHA
estimates that approximately US$2.1 billion will need to be
invested. In comparison, an additional US$4.7 billion may be
required by the plants in medium need.

In order to secure reliable, efficient, and safe electricity
generation from the plants in the high-need category, IHA
estimates that approximately US$2.1 billion will need to be
invested. In comparison, an additional US$4.7 billion may be

Table 02. Overall estimates of investment need for total capacity
assessed in the study with high and medium needs for modernisation

|  | High need | Medium need |
| --- | --- | --- |
| Installed capacity assessed in in the mapping\* | 4.6GW | 10.1GW |
| % of overall African hydropower fleet (38.5GW)^{6}$ | 12% | 26% |
| Estimated investment need based IHA benchmark modernisation cost\*\* | Approx.US$2.1 billion | Approx.US$4.7 billion |
| Indicative capacity upgrade associated with complete modernisation project^{7}$ | 0.23GW-0.53GW | 0.51GW-1.17GW |

- This total includes power plants for which data were received directly from the owners and plants for which only
  secondary data were available.
  \\*\\* The cost figures shown in this table are high level estimates to provide a relative sense of the magnitude of

secondary data were available.
\\*\\* The cost figures shown in this table are high level estimates to provide a relative sense of the magnitude of
modernisation costs but would be subject to a more stringent and detailed cost estimating process if a project is
to proceed to the next phase.

From a capital requirement perspective, modernisations
8
are less intense than greenfields projects. This level of
investment would not only secure the availability of over
14.7 GW installed capacity, enhance plant flexibility, reduce
maintenance costs, enhance water management and
enable safer operations of the existing fleet but would also
increase the existing generating capacity. The replacement
of outdated, deteriorated, or damaged electromechanical
components could increase the installed capacity of the
fleet between 740 MW and 1,700 MW, thanks to the improved
efficiency and increased power capability of modernised
systems.

Investments are, therefore, fundamental to securing these
plants' ongoing productivity over the following decades
and should be seen as an immediate priority to achieve
decarbonised economic development and secure a resilient
fleet capable of operating under more extreme weather
conditions triggered by climate change. A modern and
efficient hydropower fleet will provide clean and reliable
electricity and offer grid stability and flexibility services,
which are necessary to enable the expected large-scale
deployment of wind and solar energy.

From an environmental & social perspective, modernisation
to increase efficiencies, replace equipment, and rectify
ageing infrastructure issues would not instigate an adverse
change in the project's impacts. In fact, these projects are
often a great opportunity to implement measures that can
improve the E&S footprint of the plant and its operations.
Examples of these measures are the introduction of fish
ladders, the adoption of improved turbine seals which
eliminate lubricant leakage and a general improvement of the
health and safety condition of the personnel working in the
plant.

* * *

hydropower reservoirs, where it may be feasible and
economically viable to do so as has been demonstrated by
numerous international projects9. Floating solar technology
located on hydropower plant reservoirs can be successfully
implemented, taking advantage of existing grid infrastructure
to reduce costs, whilst complementing the energy
production of plants.

During the mapping exercise data, were gathered for 26
hydro reservoirs to assess potential suitability for floating
solar PV (FPV). This led to identifying 11 candidate sites where
floating solar hybrids could be developed. Introducing a
solar-hybrid system could help support generation shortfalls
during drought conditions and provide a ‘quick win’ given
their relatively short deployment timescales.

The result of this study represents a valuable starting point
on which the AfDB can build a comprehensive project to
modernise the African hydropower fleet. The recommended
next step is to further intensify the dialogue with the
owners, particularly in those high-need plants where IHA’s
assessment serves as a pre-feasibility study. These are plants
in urgent need of modernisation where the owners or the
concessioners have demonstrated interest in the opportunity
to cooperate with the AfDB in the near future through their
collaboration with the IHA during the course of the study.

The goal of this dialogue should be to understand the scope
of works further. The feasibility and the financial needs for
the selected projects, also consider any potential additional
barriers (e.g. financing or environmental & sustainability
(E&S)) as well as other opportunities that could be included in
a proposed modernisation.

Report structure

The report is structured as follows:

PART 02 - Methodology and results of the
Africa modernisation study

Report stucture

Section 05
presents an overview of the hydropower
sector in the African contest and describes
the scope of the study.

Section 01
presents an overview of the hydropower
sector on a global level.

Section 02
describes the main drivers and benefits
associated with the modernisation of ageing

power plants.

Section 06
outlines how the data were collected and
presents the process and the methodology
followed to determine the rehabilitation
needs of each station.

Section 08
provides a review of the ESG impacts of the
typical modernisation projects identified in
this project.

* * *

Africa Hydropower Modernisation Programme Continent-wide mapping of hydropower rehabilitation candidates

# Part 01

## General modernisation background information

### 1.00 0

* * *

Section 01
background information

01.1 \| Overview of the hydropower
sector

Hydropower is globally the backbone of low-carbon
electricity generation and remains the single largest source
of renewable electricity. In 2021, it accounted for 16% of
all electricity generated across the globe, providing an
overall contribution 55% higher than nuclear and more
significant than all other renewables combined (Figure 01).
However, while most of the finances are globally directed
towards unlocking new developments, there is also a rapidly
increasing need to modernise and optimise the current fleet
of ageing assets. Indeed, as of today, circa 40% of the global
10
fleet is at least 40 years old. This will ensure that the vital
role played by hydropower is sustained and enhanced.

Figure 01. Global electricity generation from low-carbon technologies
(2021)

SOURCE IEA

Hydropower remains one of the most competitive energy
sources available. According to the International Renewable
Energy Agency (IRENA), the cost of electricity from new
hydropower projects remains amongst the cheapest
renewable energy sources with an average levelised cost
of energy (LCOE) in 2021 of 0.048 US$/kWh (Figure 02),
well below offshore wind, geothermal, bioenergy and
concentrated solar power.

* * *

Figure 02. Levelised cost of electricity of renewable energy sources
(2021)

The remaining potential for the development of new
greenfield hydropower projects is substantial. Without
including off-river pump storage hydro, circa 2,000 GW
of potential sites are left untapped, not including 550 GW
currently under development. The International Energy
Agency and the International Renewable Energy Agency
agree that to keep global warming below two °C, the most
cost-effective pathway would see at least 850 GW of new
hydropower capacity developed over the next 30 years. The
numbers are even more significant for the more ambitious
Net Zero target (limiting temperature rise to below 1.5°C),
with a total installed capacity required in excess of 2,500 GW
(almost twice today’s installed capacity).

^circ mathrm C

Figure 03. Hydropower potential capacity

* * *

The challenges faced to achieve a net-zero economy involve
not only the development of new greenfield projects but also
substantial efforts in modernising the existing fleet. Indeed,
according to the IEA, 166 GW of new hydropower capacity
is expected to come from the modernisation of the current
fleet over the next decade. It is also reported that if the
business case for modernisation is made more attractive and
if there will be sufficient water resources available to increase
turbine size, this potential could be substantially higher,
closer to 400 GW11.

Nonetheless, despite these promising figures, global
investment in modernisation remains well below the
required level. Indeed, the IEA figure shows that planned and
announced modernisation projects are estimated to cost a
total of USD 127 billion by 2030, while the minimum required
investment to replace ageing components and maintain
plants availability is estimated in the order of US$ 300 billion,
12
or 2.4x higher.

• XFLEX HYDRO – This project currently brings together
19 institutional partners with internationally-recognised
expertise (including IHA) to study and demonstrate
advanced technological solutions to extend the flexibility
of existing hydropower plant and increase hydraulic
components lifespan, using advanced software solutions
and modest technological upgrades.

• AIIB Working Paper
• Modernization of Hydropower Plants in Latin America and

01.2 \| References to global
modernisation efforts

• IHA Summary

• Modernization of Hydropower Plants in Latin America and
Caribbean – Identification and prioritisation of investment
needs; developed in cooperation with the Inter-American
Development Bank (IDB), 2020.

Previous continental studies that were conducted by the IHA
on modernisation of hydropower fleet include:

* * *

Section 02
drivers and opportunities
of modernisation

02.1 \| Overview

Beyond extending the lifetime of these assets, modernisation
represents a key opportunity for existing hydropower
infrastructure to provide benefits such as optimised power
production through improved efficiency or capacity
additions, optimised operations and maintenance (O&M),
enhanced flexibility and water services at multipurpose
hydropower sites. Modernisation projects have capital
requirements which are much less significant than greenfield
projects and generally have modest or negligible E&S
impacts.

Projects to modernise hydropower plants go further than
business-as-usual O&M and involve a more significant
re-investment in an existing asset. Although the type of
modernisation will vary on a case-by-case basis, depending
on the needs and options available for a given site, strategies
will generally fall into the following types:

projects look to extend the life of the station with repairs
or replacements of existing key electro-mechanical
components to maintain the existing operation of the units
or, in some cases, restore derated units back to their design
capacity, often improving performance. A case study is
presented in case study 1 in section 2.4.

Life extension

projects aim to improve services by increasing generating
efficiency, uprating installed power capacity, expanding
the operating regime or re-equipping a site with new
technologies, e.g. to operate under more extreme variations
in streamflow or to accommodate greater penetration of
variable renewable technologies into the energy mix; while
also extending the life of the station. Case study 2 in section
2.4 shows an example profile.

Major upgrade/uprate
projects aim to improve services by increasing generating

can also play a central role in any modernisation scheme
and be integrated within any of the listed categories. Such
projects focus on updating control systems, monitoring
and communication systems, and introducing state-ofthe-art digital analytics to optimise operations and provide
preventative maintenance.

* * *

With different types and scales of projects, there can be
many reasons for modernising an existing hydropower
station. This review looks to introduce the main drivers and
opportunities for modernisation projects.

Figure 04. Diagram of a hydropower station displaying key features

KEY
1 Reservoir
2 Control gate
3 Trash rack
4 Intake
5 Penstock
6 Powerhouse
7 Generator
8 Turbine
9 Draft tube
10 Outflow
11 Spil way
12 Transmission

* * *

02.2 \| Plant ageing

All hydropower stations age over time, causing a degradation
in reliability and performance. Hydraulic generating units
all undergo some degree of mechanical degradation over
years of operation; typically, the unit’s generator is the first
major component to exhibit signs of wear and tear from
high thermal or mechanical stresses (rotors and windings),
generally followed by the turbines (rotating blades, guide
vanes, etc.) and eventually civil structures will show signs of
degradation over longer timeframes, sometimes introducing
issues with the safety of the facility. Studies published by
International Financial Institutions (IFI)s, Original Equipment
Manufacturers (OEMs) and research organisations describe
the physical processes which lead to degradation as well
as remedial measures taken in modernisations in more
13,14,15,16,17,18
detail.

Figure 5 presents the lifespans of the major systems of a
hydropower station based on assessments applied in a
World Bank study. The blue bars show the years each type of
system is in good working condition after entering service;
the dark red bars show subsequent years of fair performance;
and above this threshold, the systems are expected to be in
poor condition, shown in yellow.

Figure 05. Indicative average lifespans of major systems in a
hydropower station

Electrical and controls

Batteries and direct current (DC) equipment

High voltage, switchgear, auxiliary
electricals, control equipment

Generators and transformers

Gates, valves, cranes, auxiliary mechanical
systems

Mechanical

Civil structures

Turbines

Powerhouse, water catchment, spilway,
penstocks, steel linings, roads, bridges

Dams, canals, tunnels, caverns, reservoirs,
surge chambers

SOURCE based on data from a World Bank study by Goldberg and Espeseth, 2011

As shown, the electrical auxiliary and control systems
are typically replaced or updated first, often due to
obsolescence. The major electro-mechanical drivetrain
components such as hydraulic turbines, generators and
transformers generally are modernised 30 to 45 years
after the original commissioning date depending on
several factors, including the original materials used in
manufacturing components, operating conditions and
site conditions. Degradation rates can be accelerated for
different reasons:

* * *

• Improper equipment maintenance, either through lack of
training on O&M practices or resources, will accelerate
the end of life of hydropower facilities.
• High sediment loads will lead to accelerated plant

• High sediment loads will lead to accelerated plant
degradation, particularly in the turbines.
• Changes in modes of operation, such as when machines

• Changes in modes of operation, such as when machines
are more extensively used for peaking or the provision
of grid support services, can also cause higher stresses
on rotating machinery and electrical systems, therefore
reducing their lifetime.
• More extreme weather events such as cyclones or floods

• More extreme weather events such as cyclones or floods
or damage caused by social unrest.

02.3 \| Performance recovery

This can increase business risk and, depending on the
owner’s appetite for risk over time, determine when
modernisation is required. Moreover, as hydropower is
commonly the lowest marginal cost unit in a power pool in
many markets, failing to modernise assets adequately can
have detrimental impacts. Suppose the station is operating
significantly below rated capacity for long periods. In that
case, the shortfall in electricity supply may be replaced by
more expensive thermal alternatives resulting in increased

greenhouse gas (GHG) emissions and costs for the utilities
and customers.

Modernisation can mitigate this risk by repairing and
replacing old equipment to reduce outages, improve
availability and, in some cases, increase power output. A
study undertaken by an OEM showed that life extension
projects where turbine runners are replaced could increase
or recover overall plant efficiency by 3 per cent and
potentially up to 6 per cent or more; while larger projects
involving the upgrade of turbine-generator units can increase
19
installed capacity by up to 40 per cent.

02.4 \| Capacity and technology
upgrades

In some cases, opportunities may exist to expand or update
existing facilities' installed capacity and overall efficiency.
In these cases, installed capacity (MW) may be increased
by replacing turbine runners with higher capacity units and
20
optimised systems. Technology developments are a key
factor in hydropower modernisations. Old systems can be
replaced with state-of-the-art equipment, bringing benefits
21, 22
for operators. From turbine generators to spillway
gates, equipment installed over 30 to 40 years ago can be
retrofitted with new components optimised for improved
efficiency and reduced environmental impact, thanks to
23,24,25,26
advanced manufacturing and materials. Technology
upgrades can also bring forward the decision to modernise a
project.

* * *

Case study 01. Kpong, Ghana

Type of modernisation
Life extension

Year of completion
2020

Type of facility
160 MW run-of-river plant

Owner
Volta River Authority (VRA)

Picture
ANDRITZ.com, © VRA.

Having operated the plant for about 30 years, the Volta River Authority decided to undertake
a significant retrofit to extend the plant's life and increase its availability. The modernised
plant will provide Ghana with a reliable and clean energy supply for another 30 years,
contributing 4.3% of the country’s total electricity mix.

7. Benefits: improved availability and reliability of electricity supply, reduced plant failures,
   life extension, optimised operations, and improved VRA’s competitive position in national
   c
   and international markets.

8. The units were completed sequentially in 2016, 2017, 2019 and 2020.

9. Installed capacity of the plant was maintained as before at 160 MW.


CHARACTERISTICS

Case study 02. Nalubaale, Uganda

a Information provided by VRA; b [https://www.afd.fr/fr/carte-des-projets/rehabilitation-de-la-centrale-hydroelectrique-de-kpong](https://www.afd.fr/fr/carte-des-projets/rehabilitation-de-la-centrale-hydroelectrique-de-kpong); c
[https://www.andritz.com/hydro-en/hydronews/hn34/kpong-ghana](https://www.andritz.com/hydro-en/hydronews/hn34/kpong-ghana)

Type of modernisation
major upgrade

Year of completion
2000

Age of facility when
modernised
Commissioned in 1954; approx.
46 years.

Owner
Uganda Electricity Generation
Company Ltd. (UEGCL)

Picture
© UEGCL.com

References

In the 1990s, the Nalubaale station was refurbished to repair concrete issues caused
by Alkali-Aggregate Reaction (AAR) in the powerhouse and main dam and to address
accumulated wear from a decade of civil disorder. During the repairs, the output power of all
ten generators was increased, bringing the Nalubaale Power Complex’s generating capacity
to 180 MW. The station is adjacent to the 200 MW Kiira hydropower plant built in 2003, and
together the Nalubaale-Kiira complex supplies a third of Uganda’s electricity.c

1. From 1990 to 2000, each of the ten 15 MW Kaplan turbine units was upgraded to 18 MW;
   increasing total installed capacity by 20% from 150 MW to 180 MW.a

2. Sinohydro Corporation oversaw the refurbishment of the concrete dam and powerhouse

3. Full environmental and social impact assessments (ESIA) carried out to ensure
   b
   compliance.
   a

4. Annual generation: 724 GWh in 2021.


CHARACTERISTICS

1. From 1990 to 2000, each of the ten 15 MW Kaplan turbine units was upgraded to 18 MW;

2. Benefits: Increasing power capacity by 30 MW, life extension of components, reduced environmental impact, increased availability, higher annual output & reduced O&M costs.


environmental impact, increased availability, higher annual output & reduced O&M costs.
8\. The plant is coming up for its subsequent rehabilitation and optimisation, with feasibility
studies completed and project implementation planned from 2025. The program aims
to continue to address the long-term effects of AAR on the dam, refurbishment of
a
electromechanical equipment, and structural enhancements for flood mitigation.
9\. There had been no spilling since 2000 following the upgrades. However, recent flooding

9. There had been no spilling since 2000 following the upgrades. However, recent flooding
   events in 2020 have raised concerns about the capacity of the spillway as well as the
   safety of the dam.

10. UEGCL is studying the feasibility of installing floating solar PV on its hydro reservoirs,

11. UEGCL is studying the feasibility of installing floating solar PV on its hydro reservoirs,
   including Nalubaale.

12. Find further details on the operations & maintenance (O&M) strategy, issues and
   modernisation in a report prepared by IHA for the World Bank’s O&M Handbook for
   d
   Hydropower published in 2020.


References

There are many other examples of hydropower upgrade
programs in Africa, such as Akosombo, Upper Kafue Gorge
and Kariba North Bank in Zambia, where major turbine
29
retrofits increased capacity. Other projects include the
Roseires hydropower plant in Sudan where measures were
implemented to enhance sediment handling capacity by
increasing the height of the dam by 10 m to raise its storage
capacity from 3 to 7.4 billion m3 and thereby increasing
30
energy generation by 50 per cent.

02.5 \| Policy and markets

The decision to extend the life and potentially upgrade a
hydropower station will typically be influenced strongly by
the overall project economics, which is primarily driven by
modernisation costs, electricity prices and market design. At
the national level, where there is a risk of decommissioning
old hydropower stations and potentially losing reliable,
renewable generation capacity, governments may also
develop enabling policies to encourage re-investment.
Typical cost benchmarks for hydropower modernisation
projects are discussed in section 6.1.

References
a Information provided by UEGCL; b [https://tractebel-engie.com/en/references/nalubaale-and-kiira-hydropower-plants](https://tractebel-engie.com/en/references/nalubaale-and-kiira-hydropower-plants)
c [https://allafrica.com/stories/201208060974.html](https://allafrica.com/stories/201208060974.html) ; d [https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-](https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-)
Case-Studies.pdf?sequence=4&isAllowed=y

• promote and increase investments in electricity
production, transmission and distribution infrastructure;
• create a regional regulatory framework for pooling energy

In Africa, cross-border power trading has been taking place
for many decades, with bilateral power trading arrangements
dating back to the 1950s and 1960s. During the 1990s,
energy sector reform and liberalisation of national grids
were undertaken in many African countries and set the
stage for the development of power pools, beginning with
the Southern Africa Power Pool (SAPP), followed by the
development of Central (CAPP), Western (WAPP) and Eastern
power pools (EAPP); all with similar objectives31:

• create a regional regulatory framework for pooling energy
resources, including the establishment of common
standards, rules and monitoring mechanisms;
• coordinate the long-term energy development in the

* * *

While these power pools have been functioning successfully
for some time, specific challenges in Africa have developed
over time. Whilst the SAPP has been the dominant player,
led by well-established markets in South Africa, the lack
of a champion in the WAPP and EAPP appears to have
significantly limited their progress. This is evident in Sub-
Saharan Africa, where existing hydropower is dominant and
future growth in new hydropower is underway, but a well-
32
established power trading market is still evolving.

The table 03 summarises those countries within each power
pool with over 100 MW of hydropower capacity considered
under the Continental Mapping study; and comments on
some key trends that have evolved relative to their respective
energy markets and major hydro suppliers.

Case study 03. Mount Coffee, Liberia

Type of modernisation
total redevelopment

Picture
openknowledge.worldbank.

Costs
US$ 357m

Type of facility
88 MW run-of-river plant

After being destroyed in the Liberian Civil War in 1990, a complete rebuild of the Mount
Coffee Hydropower station was completed in 2017, increasing its pre-war 64 MW capacity
to 88 MW following the modernisation. The restoration brought much-needed power
online, providing 1 million people with a stable electricity supply, replacing fossil-fuel diesel
c
generators and helping reduce electricity prices in Liberia.

1. Rebuilding dams and associated civil works, rehabilitation of the spillway and gates,
   intake structure, and powerhouse civil structure & replaced the electromechanical
   equipment.
2. The rehabilitation of the dam began in 2012, though with the Ebola virus in 2014 and local

CHARACTERISTICS

2. The rehabilitation of the dam began in 2012, though with the Ebola virus in 2014 and local
   access challenges with poor road infrastructure, works were delayed by a year. Following
   partial completion of the intake and spillway structures, commissioning of the four 22 MW
   d
   Francis units was done in 2016-2017, supplied by Voith Hydro.

3. As the facility was rendered inoperable for years, the original owner (LEC) lost its in-

4. As the facility was rendered inoperable for years, the original owner (LEC) lost its inhouse expertise in operating the hydropower plant. In 2016, a contract was assigned to
   an outside agency (HOI) to operate and maintain the plant while carrying out theoretical
   and hands-on training to qualify O&M staff. Further information on the O&M model was
   c
   published in 2020.

5. Annual generation: 223 GWh in 2020.

6. Funded by the Liberian and Norwegian governments, European Investment Bank, German
   development bank KfW, and the Millennium Challenge Corporation; at a total cost of
   c
   US$357m.

7. Benefits: Improved efficiency and capacity by restoring 88 MW, optimised operations, life


a
4\. Annual generation: 223 GWh in 2020.

6. Benefits: Improved efficiency and capacity by restoring 88 MW, optimised operations, life
   a
   extension, training on O&M practices, and improving climate resilience.

7. Safety: mitigation of upstream and downstream flood impacts

8. Safety: mitigation of upstream and downstream flood impacts

9. Although the plant is now operating well, there is a ten-year plan to add two more units,


a Information provided by LEC (Mount Coffee); b [https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-](https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-)
Case-Studies.pdf?sequence=4
c [https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html](https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html) ; d [https://voith.com/](https://voith.com/)

8. Although the plant is now operating well, there is a ten-year plan to add two more units,
   which would expand installed capacity from the current 88 MW to 132 MW. There are
   other plans under consideration for a second hydropower plant. a Furthermore, a 90
   MW solar farm is planned in Liberia, of which 20 MW will be built at the Mount Coffee
   a
   hydropower plant expected by 2024.

Case-Studies.pdf?sequence=4
c [https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html](https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html) ; d [https://voith.com/](https://voith.com/)
hydro-in-africa-en/mount-coffee.html

* * *

Table 03. African regional power pools and key hydropower trends

Regional Power Pool

Southern Africa (SAPP)

Linked countries with >100 MW of ageing hydropower in scope

Zambia, South Africa, Mozambique, Zimbabwe, Namibia \*Planned members: Angola, Malawi, Tanzania

Key trends & hydropower plants (HPPs)

Hydro plants in the Zambezi river basin have undergone or are undergoing major modernisations or expansions,
e.g. at the Kariba, Kafue Gorge & Tedzani Falls HPPs33

Cahora Bassa HPP in Mozambique generates significant energy for the SAPP and has facilities due for
modernisation

HPPs in South Africa also play a critical role, including Drakensberg pumped storage scheme which helps
34,35
provide back-up reserve to the network; recently with units modernised

Angola, Malawi and Tanzania are not yet integrated and efforts are at an advanced stage to link the three
countries into the power pool36,37

In Malawi, modernisation will be needed to allow existing HPPs to interface with a new interconnector being
constructed to Mozambique

Regional Power Pool

Egypt, Ethiopia, Kenya, Sudan, Uganda

38
Ethiopia has a number of existing hydro facilities in need of modernisation that play a major role in the EAPP.

In Egypt, the major Aswan HPPs are coming up for modernisation40

Regional Power Pool

Key trends & hydropower plants (HPPs)

Linked countries with >100 MW of ageing hydropower in scope

Recently, the World Bank financed a 667 km HVDC line from Kenya through Tanzania to Zambia; to link EAPP &
SAPP39

Key trends & hydropower plants (HPPs)

Nigeria, Ghana, Côte D’Ivoire

The Kainji & Jebba HPPs are key to the success of power trading in Nigeria, which has low electrification rates
(<50%). The 'North Core' transmission project soon to be completed will link Nigeria-Niger-Benin-Burkina Faso41

Ghana and Côte d’Ivoire are key drivers of integration because of their regional ambitions & central location in
the region.

Kpong & Akosombo HPPs in Ghana were upgraded; while plans for Kossou, Buyo & Taabo HPPs in Côte D’Ivoire
are underway

Regional Power Pool

Linked countries with >100 MW of ageing hydropower in scope

Modernisation & expansion of the Inga HPPs in DRC will play a strong role in the regional pools (CAPP, SAPP)

Central Africa (CAPP)

Key trends & hydropower plants (HPPs)

DRC, Cameroon, Gabon

Angola’s location could also trade supply into CAPP

Linked countries with >100 MW of ageing hydropower in scope

In all regions and countries of Africa where existing
hydropower plays a key role, such as Ethiopia, Nigeria and
Uganda, the success of those markets will be tied firmly to
the maintenance of existing hydropower capacity and the
continued development of new hydropower where feasible,
to ensure that these regions can generate an energy surplus,
along with ensuring that adequate transmission is in place for
cross-border power trading.

Regional Power Pool

North Africa (COMELEC)

Key trends & hydropower plants (HPPs)

As the primary source of renewable energy in Morocco, the existing hydropower assets are due for
modernisation

* * *

Electricity markets can therefore act as a key driver for
modernisation decisions, whether heavily liberalised or, as
is more common in an African context, still mainly driven by
national-level decisions. Ongoing reforms in many markets
will have to recognise better and remunerate the essential
role hydropower plays in supporting grids and offering
balancing services to the system. In parts of both North and
South America, Europe and Australia, hydropower units are
already moving away from traditional baseload generation
to modes of operation which accommodate and support
43
a changing energy mix. This continues to make use of
hydropower’s unique characteristics as a dispatchable power
source, but can also lead to higher operating costs and the
44
need to re-invest in plants.

Broader policy changes can also have a direct or indirect
impact, particularly regarding climate policy. For example,
nearly all African countries have committed to action
on climate change in ratified Nationally Determined
Contributions under the Paris Agreement, agreeing to reduce
their greenhouse gas emissions and build resilience. Such
policy commitments will lead to an increased emphasis on
low carbon generation, which can be directly supplied by
hydropower or, in the case of variable solar or wind, enabled
by hydropower’s flexible characteristics, which can be further
enhanced through modernisation (see section 2.6).

02.6 \| Power flexibility, energy
storage and variable renewable
energies deployment

As electricity markets and transmission grids evolve45, power
flexibility and energy storage are becoming increasingly
essential and strongly support the need for hydropower
modernisation. According to IRENA projections, by 2050,
the fleet of wind and solar plants in Africa and the Middle
East may reach the record-breaking level of 1220 GW of
installed capacity, 36x more than today46. It is, therefore,
natural that, as of today, many generators and transmission
system operators are looking for ways to improve frequency
control and other ancillary services to support the electricity
grid; this can require hydropower units to operate over
an extended range, requiring quicker response ramping
capability, part-load and fast stop/start capabilities amongst
other improvements. If existing stations were not originally
designed for these services, components may need to be reengineered and replaced.

Existing and future pumped hydropower storage projects
continue to be integral in Africa. In South Africa, Eskom’s
40-year-old 1000 MW Drakensberg pumped storage
facility was recently modernised, with upgrades to all three
47
units, to ensure reliable operation for the next 40 years.
Another example is in Morocco, where the Office National
de L'Electricite (ONEE) has commissioned a study of the
465 MW Afourer hydropower complex, aimed at optimising
operation in both the pumped storage and conventional
48
hydropower mode of the complex. The International Forum
on Pumped Storage Hydropower (PSH) provided global
recommendations to support the increased deployment of
49
PSH.

* * *

and efficiency of pumped storage, especially in markets
where network stability is influenced by asynchronous wind,
solar and battery technologies. Battery hybrids can also
improve energy storage services at existing hydropower
stations, whereby the battery provides fast frequency
response over short timescales (2 seconds or less). In turn,
hydro-generators provide network regulation & ramping
services over longer timeframes. Using battery electronics
for frequency control can also relieve control requirements
and mechanical wear and tear on hydro machinery.

These strategies add to the range of options available for
hydropower. They can also give access to revenue streams
that are offered (or may be offered in the future) for power
balancing services, thus helping to harness hydropower’s
full potential. When planning modernisation projects, both
the benefits and added costs of flexibility technologies will
need to be increasingly considered and weighed against
51,52
alternative approaches.

02.7 \| Digitalisation of systems

The digitalisation of hydropower technologies and operation
and maintenance practices is well established in many more
mature energy markets and has become a key feature of
modernisation programmes. Projects now include installing
new digital controls, intelligent condition monitoring
systems, remotely operated systems, and supervisory control
and data acquisition systems to digitalise the operation and
management of existing stations.

02.8 \| Hybridisation of
hydropower plants

Hybrid concepts are gaining interest, whereby different
renewable technologies complement each other and work
more efficiently. Installing FPV onto existing reservoirs,
in particular, provides additional renewable generation
that is low carbon and cost. FPV systems can use existing
infrastructure at the hydropower site, reducing land
acquisition and grid connection costs otherwise incurred in
greenfield solar projects. Integrating the FPV and hydropower
control systems can also provide a win-win solution; because
generating units can be run flexibly and used to back up
solar output fluctuations, thus feeding a more stable power
profile into the grid network. The added solar output can also
reduce requirements on hydro generation in daylight hours
and can help to preserve reservoir storage levels during dry
periods.

Case study 04. Floating solar PV, Bui Dam in Ghana

* * *

Project
Solar hybrid at Bui Hydro

Solar hybrid at Bui Hydro
Generating Station

Year of completion
2020

Type of facility
404 MW storage hydro plant,
with 1 MW floating PV, plus 4
MW under construction and
plans for >50MW.

Age of facility
Hydro commissioned in 2013;
Floating PV in 2020

Owner
Bui Power Authority (BPA)

Pictures
© Bui Power Authoritya

With the government of Ghana’s commitment to increase

penetration of renewables by 10% by 2030, BPA expanded
the existing switchyard at its Bui hydropower plant to
accommodate 250 MW of solar PV – for the creation of a
hydro-solar PV hybrid (HSH) system within the Bui enclave.
In 2020, a pilot 1 MW floating PV array was installed on the
reservoir alongside a 50 MW land-based solar PV, which was
also commissioned. When complete, the HSH system aims to
augment and preserve the Bui reservoir by generating solar
power.

KEY COMPONENTS

Panels

2,500 PV panel units for the 1 MW floating PV pilot, to be
upscaled to 10,000 units (Bi-Facial Mono-crystalline PV
2
module); the rating per unit is 405 W with surface area of 2m
and 30kg weight.

Inverters

4x 250kW size

Transformer

Floats

KEY BENEFITS
1 MW floating solar pilot had a footprint of 1.7 acres (6880
m2), which is around a 50% saving on space compared to an
equivalent 1 MW of land-based solar array.

primarily due to the cooling effect of the water on the solar
panels.

Water is also conserved for larger arrays due to reduced
evaporation from the reservoir.

IMPLEMENTATION

Phase 1 pilot commissioned in 2020;
Phase 2 expansion to 5 MW floating PV expected complete

Phase 2 expansion to 5 MW floating PV expected complete
by end of of 2022;

Phase 3 subject to a successful implementation of the 5 MW
system, BPA aims to upscale to >50MW.

1. Engineering, Procurement and Construction (EPC) +
   financing
2. Installation was done by in-house staff at BuiPower.

Project model

1. Engineering, Procurement and Construction (EPC) +

2. Installation was done by in-house staff at BuiPower.

3. Power is transmitted via the Bui switchyard to Ghana’s

4. Power is transmitted via the Bui switchyard to Ghana’s
   National Interconnected Transmission System (NITS).

5. BuiPower has broader plans to develop a 250 MW solar

6. BuiPower has broader plans to develop a 250 MW solar
   PV facility at the site (including the 50 MW co-located
   system on land) and has also earmarked six other
   locations for PV projects in the region.


a Information provided by LEC (Mount Coffee); b [https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-](https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-)
Case-Studies.pdf?sequence=4
c [https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html](https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html) ; d [https://voith.com/](https://voith.com/)

References
a Information provided by LEC (Mount Coffee); b [https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-](https://openknowledge.worldbank.org/bitstream/handle/10986/33313/Six-)

c [https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html](https://www.ft.com/partnercontent/voith/mount-coffee-hydropower-plant-raised-from-the-ruins.html) ; d [https://voith.com/](https://voith.com/)
hydro-in-africa-en/mount-coffee.html

* * *

02.9 \| Climate resilience and
hydrology

Climate resilience is a growing concern, with hydrological
variability now being considered in hydropower
modernisation projects. Greater weather extremes will affect
hydropower infrastructure in climate-sensitive regions and
may require investment in adaptive measures. For example,
southern Africa is likely to experience a drier climate with
more frequent incidences of low precipitation, while east
Africa is projected to experience a wetter climate with more
54
frequent heavy rainfall.

Climate change impacts on existing and future hydropower
projects in Africa will unquestionably result in the need
for additional resilience measures, which could range
from enhanced flood protection to sediment management
strategies, improved dam safety measures, including early
warning systems, and structural improvements to river and
55
reservoir areas. Hydropower facilities may also provide
increased protection for communities via modern and
well-maintained hydropower dams and facilities which can
offer important flood protection or water storage services
during extreme meteorological events. Climate change
may also result in the potential for increased generation in
some regions. A recent study on the Landscape of Climate
Finance in Africa by the Climate Policy Initiative identified
that hydropower systems in the eastern Nile, Niger and Volta
basins could experience potential revenue increases of 20-
140% if climate change scenarios are integrated into design
56
and building.

Other specific examples include sediment management
strategies applied at the 280 MW Roseires hydropower plant
in Sudan and as well at the 130 MW Kapachira facility in
57,58,59
Malawi.

Box 01. Hydropower Sector Climate
Resilience Guide

To facilitate the development of hydropower
infrastructure that can withstand the risks of
variable climatic conditions, the Hydropower
Sector Climate Resilience Guide was
developed and launched in May 2019. It is the
first sector-specific climate resilience guide
providing a practical and helpful approach for
identifying, assessing and managing climate
risks to enhance the climate change resilience
of new and existing hydropower projects.

The six-phase methodology can be applied to
projects of all types, scales and geographies
and looks at climate risk screening, data
analysis, climate stress testing, climate risk
management, monitoring, evaluation and
reporting.

* * *

the turbine design to adapt to lower minimum flows or
potentially decommissioning older units. Conversely, plant
modernisation would consider upgrades to increase unit
capacity where possible or even additional units if flows
are growing. In other cases, dam, reservoir and spillway
upgrades may be required if average river flows have
changed significantly over the decades and there is a greater
risk of extreme flood events in the future.

In a special report prepared by the International Energy
Agency (IEA), projections were made about the impacts of
climate change on hydropower projects in various regions
of Africa. Under a range of scenarios, the regional mean
hydropower capacity factor60 is projected to decrease by
the end of the century due to climate change. The analysis
indicated significant spatial variation in climate change
impacts regionally in Africa. For example, the hydropower
capacity factor in Morocco is projected to decrease slightly;
while it increases slightly for projects located in the Nile
basin (including Egypt, Sudan, Kenya, and Ethiopia) under a
scenario that assumes global warming of less than two°C by
61
2100.

02.10 \| Socio-environmental
impacts

In some regions, climate change is already showing strong
indications of impacting water availability and season inflow
variability, with declining hydro output in Morocco in recent
years and droughts in parts of Angola. The data and tools
available to accurately model hydrological impacts vary by
country and region. The World Meteorological Organization’s
2022 State of Climate Services: Energy62 report set out
several approaches by different National Meteorological and
Hydrological Services providers, including, for example,
Tajik Hydromet in Tajikistan. With support from several
international agencies, Tajik Hydromet can now apply
new techniques to provide more targeted information to
Tajikistan’s state-owned power utility to support the safe and
efficient operation of hydropower plants.

Sustainability and environmental and social impact can be
key drivers for modernisation, particularly in large-scale
redevelopments. New environmental technologies are also
being increasingly adopted to improve natural habitats, water
quality, fish management and reduce detrimental impacts on
63
ecology upstream and downstream of hydropower sites.

For existing multipurpose hydropower schemes in Africa,
water services can potentially be improved as due to
modernisation by increasing reservoir capacity or by adding
or improving existing irrigation services, flood management
and downstream flow regimes. Hydropower sites and
their operations can also impact a region’s public water
resources, meaning changes expected from modernisation
projects must be considered at the planning stage and in
collaboration with the water authority.

For example, in the case of the modernisation of the
Nalubaale and Kiira hydropower plants in Uganda,
Environmental Social Impact (ESIA) / Compliance
Assessment and Environmental & Social Risk Screening/
Initial Impact Assessments were considered for all possible
64
options. Similarly, the ongoing modernisation of the
Kainji-Jebba complex in Nigeria involves full consideration
of environmental & social impacts and benefits from the
65
recovery and rehabilitation of these facilities.

* * *

Box 02. Hydropower sustainability standard
& tools

Developed through a multi-stakeholder process,
hydropower operators and developers can now
demonstrate their projects' environmental, social
and governance (ESG) performance using the
Hydropower Sustainability Standard.

Projects can be certified against defined
international goods and best practices using
Hydropower Sustainability Tools. The tools provide
a common language for governments, civil
society, financial institutions and the hydropower
sector to discuss and evaluate sustainability
issues in hydropower projects. There are three
complementary tools:

• The Hydropower Sustainability Guidelines
on Good International Industry Practice
(HGIIP) define processes and outcomes that
constitute good international industry practice.
Performance can be measured through two
complementary tools:
• The Hydropower Sustainability Assessment

• The Hydropower Sustainability Environmental,
Social and Governance Gap Analysis Tool (HESG)
checks for gaps against the good practice on key
topics and includes a gap management plan.

02.11 \| Contractual limits and
regulations

Many large-scale hydropower facilities operate under longterm concession agreements held with a local authority or
power off-taker and sell the electricity generated to a third-
66
party buyer via a power purchase agreement (PPA). The
expiry of an existing concession or a PPA can be a key driver
for re-investing in an existing asset. For a station nearing the
end of its life, renewal of the concession agreement may
be a key factor to make sure that the current operator is
67
sufficiently incentivised to start a modernisation project.

Regulatory risks affect decisions around modernisation
projects across several areas, notably:

Electricity sector legislation

can guide re-licensing requirements for power stations;
grid network rules can affect operating and dispatch
requirements; and typical market structures and publicprivate models implemented in the power sector (PPAs,
concessions, etc.). Governments may also support reinvestment and modernisation, mainly where hydropower
plays a significant role, as in Norway and Switzerland.
Furthermore, in the case of FPV hybrid, there may be
68
additional regulatory factors to consider.

Water laws and policies
can affect the usage of water resources. Water authorities

requirements can come into force or be updated, obligating
owners to refurbish existing hydropower sites to meet
stricter limits.

An Investors Guide to Hydropower in Africa, published
in 2021 by international law firm Addleshaw Goddard
with support from IHA, gives an overview of these areas and related legal issues. Country profiles are included
on Ethiopia, Nigeria, Malawi, Zambia, Uganda, Morocco,
Mozambique, Cameroon, Ghana, and Rwanda – many of
which have ageing hydropower stations and modernisation
69
needs. The World Bank’s Operation and Maintenance
Strategies for Hydropower, published in 2020 with support
70
from IHA, also provides further information on O&M models.

Section 03
E&S implications associated
with modernisation
projects

The focus of this section is to discuss the main environmental
and social (E&S) implications associated with modernisation
projects. Hydropower projects provide an interface between
society and the environment. Modernisation projects are no
different. They aim to protect people from natural hazards,
like droughts or floods. They also allow people to benefit
from what nature offers – renewable and clean electricity that
drives socio-economic development and enables wind and
solar power with storage services – by maximising the output
of existing infrastructure.

* * *

The Hydropower Sustainability (HS) Standard offers the
leading global assessment framework to evaluate the E&S
performance of hydropower projects. Based on over two
decades of implementation, the HS Standard is a proven
and robust methodology to address E&S challenges in
hydropower and its framework has already been used to
assess the potential E&S impacts of a modernisation project
71
in Sweden. It covers the following 12 sections, which are
aligned with the International Finance Corporation’s (IFC)
Environmental and Social Performance Standards and the
World Bank’s Environmental and Social Framework:

01. Environmental and Social Assessment and Management
02. Labour and Working Conditions
03. Water Quality and Sediments
04. Community Impacts and Infrastructure Safety
05. Resettlement
06. Biodiversity and Invasive Species
07. Indigenous Peoples
08. Cultural Heritage
09. Communications and Consultation
10. Governance and Procurement
11. Hydrological Resource
12. Climate Change Mitigation and Resilience

Hydropower projects can have several sustainability risks
and opportunities. These are often site- and project-specific
and must be understood in detail to apply best management
practices. This applies equally to modernisation projects.

03.2 \| General considerations
about the environmental & social
implications of modernisation
projects

works on electrical, electromechanical and civil components
that help ensure the long-term efficiency of the projects.
Generally, and in the HS Standard, many E&S considerations
around major modernisation exercises or refurbishments
for operating hydropower projects are typically assessed
using the Preparation Stage and Implementation stage
tools. This is because many challenges facing modernisation
projects are similar to those in the design and construction
stages of a new build facility, such as altered flow regimes,
sedimentation and erosion issues, occupational health and
safety concerns, and potential legacy issues.

Minor works to increase efficiencies, replace equipment and
rectify ageing infrastructure issues could be considered
normal asset management practice for operations and
usually would result in positive changes in the E&S indicators
of the project.

Other examples of E&S impacts associated with rehabilitation
works that should receive careful consideration include
but are not limited to: the use of land for brief facilities
and access roads, the temporary diversion of river waters
from river sections, the discharge of pollutant drainage
from camps or the discharge of hazardous substance in the
surroundings of the plant, noise and safety risks faced by
local communities and possible conflicts between workers
and local community members.

Beyond mitigating impacts, modernisation projects can
enhance pre-project E&S conditions and even address legacy
issues that may impact the future perception of hydropower
in the country or region. The HS Standard also offers insight
into best practices to help guide ambitious project owners
in developing projects that positively impact people and the
planet. Another positive aspect is that modernisation projects
are often associated with increased electricity generation
from the target plant. This factor alone has a substantial
positive effect in supporting economic development and
improving the life quality of local communities.

* * *

Table 04 provides a non-exhaustive list of potential E&S
impacts of modernisation projects and opportunities for best
practices.

Table 04. Overview of the potential physical, biological and social
impacts of hydropower projects

| Physical | Biological | Social |
| --- | --- | --- |
| Alteration to water level around the reservoir and the downstream river | Temporary disturbance of fauna, including nesting, spawning and migration fauna | Safety risk for works during rehabilitation work |
| Disruption of sediment movement in the river system | - | Safety risk for local communities leaving in the surrounding area of the plant |
| Conversion of land for disposal of spoil, obsolete components,and disposal of waste | - | Possible conflict between workers and local communities |
| Temporary use of land for facilities and access roads | - | - |
| Emission to air(from vehicles) | - | - |
| Additional noise during project implementation | - | - |
| Temporary diversion of a river or excessive spilling | - | - |

03.3 \| Hydropower sustainability
guidelines on good international
industry practice

Older projects, developed before environmental and
social issues were considered at all, often lack adequate
environmental documentation and plans. Modernisation
projects thus offer an excellent opportunity to implement
new and modern environmental and social assessment
management approaches, with increased stakeholder
engagement and local community buy-in.

In the case of rehabilitation and modernisation projects,
it is highly recommended to follow the same steps as for
new projects in analysing possible E&S impacts during the
preparation and implementation stages. The various steps
can be summarised as follows:

Preparation stage

• Scoping and detailed assessment of potential
environmental and social impacts of the implementation
of the rehabilitation or modernisation project and the
ongoing operation of the scheme.
• Detailed stakeholder engagement on impacts and

• Planning of avoidance, minimisation, mitigation and
compensation measures for implementing rehabilitation,
modernisation, and ongoing operation.
• Planning of stakeholder engagement for implementing

• Detailed stakeholder engagement on impacts and
issues of the project, those of ongoing operations, and
proposed management measures.
• Planning of avoidance, minimisation, mitigation and

• Planning of stakeholder engagement for implementing
rehabilitation, modernisation, and ongoing operation.

Implementation stage

• Construction to the required designs to avoid and
minimise impacts.
• Mitigation of construction stage impacts, or when

• Mitigation of construction stage impacts, or when
mitigation is not feasible, compensation.

• Continuing stakeholder engagement.
• Monitoring and reporting to regulators and stakeholders.

• Monitoring and reporting to regulators and stakeholders.

Even though in the case of rehabilitation projects, the
risks of noticeable negative E&S impacts are substantially
smaller than those associated initially with the plant's
original construction, rehabilitation projects, if not
properly managed, could trigger unwanted negative E&S
consequences and lead to project delays. One important
approach to consider when implementing E&S impact
assessment and management plans is the principle of
proportionality. This principle stipulates that the extent
of mitigation required (and the associated budget) is proportional to the nature and scope of the impacts caused
by the project.

It is therefore recommended that, as part of the study to be
carried out in preparation for rehabilitation or modernisation,
all the parties involved (including plant owners, the suppliers,
and the financiers) dedicate sufficient time and resources to
the identification of possible E&S impacts associated with
the execution of the project.

A recent initiative funded by Switzerland’s State Secretariat
for Economic Affairs (SECO) made available a total of 1 million
Swiss Francs (USD 1.02m) to 40 or more hydropower projects
between 2020 and 2024 to help developers and operators
in Africa, Asia, Europe and the Americas to benchmark
and raise their social and environmental performance.
This initiative is managed by the International Hydropower
72
Association’s sustainability division.

Section 04
Modernisation cost
benchmarking

IHA undertook a high-level benchmarking exercise in 2020 to help
inform understanding of investment cost ranges. The exercise
covered 95 data points across 64 stations in 28 countries across the
world, focusing on projects greater than 10 MW in installed capacity
73
and undertaken after the year 2000. The cost information was
drawn from both publicly available sources (e.g. utilities, equipment
suppliers, engineering firms, governments and IFI reports) and cost
data supplied directly from station owners or operators. Publicly
available information presented some problems; for several projects,
cost breakdowns were not reported. In such instances, discretion was
used to determine how costs were apportioned, but where sources
were deemed unreliable, these projects were discarded.

* * *

Figure 06. The location of projects used as part of the cost
benchmarking exercise

NOTE Dark blue indicates countries were at least one project considered in the cost benchmarking exercise was located

Firstly, Capex costs were collected, recorded in US$ and
divided into three main subsystems of a station:

Civil works costs: including the civil infrastructure of a
project such as a dam, intakes, powerhouse, penstocks,
tunnels, spillways, roads and bridges.

why electrical installation costs have been combined with
mechanical installation costs to create electro-mechanical
installation costs. While generators are part of the electrical
subsystem of a station, the costs associated with turbinegenerator sets are typically reported together rather than
separately.

If required, costs were converted into US$ and then
escalated to obtain actualised costs in 2020 to make them
comparable and account for the effect of general inflation.

CAPEX = the actualised capital expenditure at year n;
n
CAPEX0 = the base capital expenditure at year 0;
i = the escalation rate;
n = the difference between year n and year 0.

n
CAPEX = CAPEX0x (1+i)
n

In line with a 2018 study which focused on estimating the
costs of greenfield projects worldwide, an escalation rate
74
(i) of 3 per cent was adopted. The escalation rate refers to
annual increases in prices associated with modernisation
projects due to inflation.

Meanwhile, civil costs bear little relationship with the
capacity of a station, reflecting that the scope of civil works
can vary widely and is more dependent on the size and
conditions of the structure. For example, civil works can
range from raising a dam’s height to rehabilitating its spillway
gates which have significantly different cost implications and
are not directly linked to a station’s generating capacity. Civil
costs can also be greatly influenced by local material and
labour costs, making estimating costs on this scale difficult.

Figure 8 shows costs as unit values per installed capacity

* * *

(US$/MW) for electrical and electromechanical installations .
The methodology used for calculating each unit value on a
US$/MW basis was:

• Electrical installation cost (US$) / Total capacity of the
station.

• Electro-mechanical installation cost (US$) / capacity
associated with the number of units impacted.

For electro-mechanical costs, the impacted units' capacity
was used as the denominator. Using the entire station's
capacity would significantly deflate the cost on a US$/MW
basis and not reflect reality.

Table 05. The range of modernisation costs on a US$/MW basis
(2020)

|  | Electrical installations | Electro-mechanical installations |
| --- | --- | --- |
| Minimum | 3500 | 91000 |
| Q1 | 24000 | 291000 |
| Median | 39000 | 432000 |
| Q3 | 53500 | 542000 |
| Maximum | 166000 | 945000 |
| Mean | 44000 | 464000 |

With an average of US$ 44,000/MW, electrical installation
costs represent a small percentage of the overall cost
associated with more complex electro-mechanical
modernisation projects (less than 10%).

Electro-mechanical costs varied by over US$ 250,000/MW
between Q1 and Q3. This can, in large part, be explained by
the scope of work. Costs at the lower end of this range were
generally associated with unit rehabilitation. In contrast,
costs of replacing and upgrading the main drivetrain
components (stators, rotors, turbines etc.) within the unit
were at the higher end. Modernisation projects that involved
the rehabilitation of units tended to record average costs
of below US$ 400,000/MW, while projects which replaced
turbines and associated components incurred costs above

Electro-mechanical costs varied by over US$ 250,000/MW
between Q1 and Q3. This can, in large part, be explained by
the scope of work. Costs at the lower end of this range were
generally associated with unit rehabilitation. In contrast,
costs of replacing and upgrading the main drivetrain
components (stators, rotors, turbines etc.) within the unit
were at the higher end. Modernisation projects that involved
the rehabilitation of units tended to record average costs
of below US$ 400,000/MW, while projects which replaced
turbines and associated components incurred costs above

turbines and associated components incurred costs above
US$ 600,000/MW.

* * *

Africa Hydropower Modernisation Programme Continent-wide mapping of hydropower rehabilitation candidates

labour costs by country, upgrades required to undersized overhead cranes, etc.

For this level of analysis, detailed costs of the varying components were not provided. More detailed information on specific components within the scope of the modernisation project (sealings, bearings, cooling system, turbine type, rotor and stator specifications, etc.) would allow for a more accurate cost estimate. Still, it would need to be based on more detailed studies, which are planned to be conducted for AHMP pilot projects.

As part of the work in the Africa modernisation mapping project, IHA has confirmed the validity of this modernisation cost benchmarking methodology and figures through consultation with two major hydropower Original Equipment Manufacturers (OEMs). Both OEMs indicated the benchmarks are reasonable and comparable with their market experience.

* * *

Africa Hydropower Modernisation Programme Continent-wide mapping of hydropower rehabilitation candidates

* * *

Africa Hydropower Modernisation Programme Africa Hydropower Modernisation Programme Continent-wide mapping of hydropower rehabilitation candidates Continent-wide mapping of hydropower rehabilitation candidates

# Part 02

## Africa – mapping of hydropower modernisation potential

* * *

Section 05
African context

Figure 08. Electricity access in Africa (2020 – % of population)

Access to electricity is a crucial factor in enabling Africa's economic
growth and social development. With energy demand growing
twice as fast as the global average, Africa has the opportunity to be
the first continent to develop its economy using mainly renewable
energy.

Despite the remarkable progress of African governments in tackling
energy poverty, the continent still needs to connect 20 million
people to the electricity network every year from now to 2030.
According to the IEA, 44% of Africa’s population was without
access to electricity in 2020, or 584 million residents, with certain
countries like DRC, Congo, Malawi, Niger or South Sudan reporting
levels above 80%.

Electricity access in Africa

* * *

The continent currently houses roughly 40 GW of installed
hydropower capacity, making it the leading renewable
resource and a primary electricity source alongside coal and
gas. Its share of total electricity generation is predicted to
75
increase from 17% in 2021 to over 23% by 2040.

As shown in Figure 09, the current pipeline of hydropower
project amounts to 118 GW and the remaining untapped
76
potential is above 470 GW.

Figure 09. Installed, under development, and remaining potential
hydropower capacity in Africa (2021)

0 5.1 \| Scope

While Africa has the highest percentage of the untapped
hydropower potential of any inhabited continent (with circa
10% utilised), 47% of the installed capacity is over 40 years
77
old, and 60% is over 30 years old. Significant opportunities
exist to improve the general and specific needs of different
assets, countries, and regions as part of a future holistic
strategy for a clean, reliable, and sustainable energy system.
This report aims to present the results of a continental-wide

mapping exercise by the IHA on the current status of the
main hydropower facilities in Africa. This work included:

• A webinar with the owners and operators of these plants
to describe the intent and the possible outcomes of this
work and how it relates to AHMP;

• A screening of the IHA’s world hydropower database;
• A webinar with the owners and operators of these plants

SOURCE IHA Status Repot 2022

• A station-level data collection to classify the status of the
assets reviewed.

Table 06. Hydropower capacity per region

| Region | Countries participating | Capacity(MW) | #stations |
| --- | --- | --- | --- |
| North Africa | Morocco, Egypt,Sudan,Algeria, | 3094 | 7 |
| West Africa | Côte D'Ivoire,Ghana,Liberia,Nigeria,Mali | 3801 | 10 |
| East Africa | Burundi,Ethiopia,Kenya,Malawi,Mozambique,Tanzania,Uganda,Zambia,Zimbabwe | 2101 | 19 |
| Central Africa | Congo,DRC,Cameroon,Gabon, | 3146 | 13 |
| South Africa | South Africa,Namibia | 12098 | 38 |

The outcome of this assignment will be a valuable tool in
the decision-making process of the AfDB in in developing of
their activities under the Africa Hydropower Modernisation
Programme.

* * *

Section 06
Methodology

06.1 \| Overview

The overall methodology for the project followed a three-step process
which is illustrated in Figure 10. Each step helped narrow down
the number of stations needing modernisation through data-based
analysis, expert advice, and feedback from station owners.

Figure 10. Overall methodology for the Continental Mapping

Activity 1
Initial screening
and data gap
analysis

Activity 2
Station level
data collection
& screening

Activity 3
Detailed
assessment

2.1
Station specific
data collection

2.2
Engagement of
owners in the
data collection

Initial workshop
session with
operators

2.3
Assessment of
data collected

3.1
Detailed
assessment of
stations with high
needs

* * *

6.2.1 Screening IHA’s database (Task 1.1)

For the initial screening, the draft database was compiled
using station data extracted from IHA’s global hydropower
database and initially filtered for stations above 50 MW
78
and over 30 years old. This reached a list of 87 stations,
totalling 24.2 GW installed capacity (more than 60% of the
African hydropower fleet). The primary station characteristics
gathered in the database included:

01. Station name

02. Installed capacity (MW)

03. Country

04. Country

05. Type of project (storage, pumped storage, or run-of-river)

06. Number of units

07. Province/ state

08. River name

09. River name

10. Location with latitude and longitude geocoordinates

11. Station owner and classification

12. Annual generation

13. Project status (operational or non-operational)

14. Station owner and classification

15. Annual generation


Figure 11. Location of the 87 plants identified for the study

* * *

Figure 12 below presents the age profile of the plants, i.e.
installed capacity and number of stations within each age
range. This illustrates that most stations within the identified
dataset were between 40 and 60 years old.

Figure 12. Age profile of the 87 hydro stations & installed capacity

AGE PROFILE OF STATIONS SCREENED

SOURCE IHA database and analysis

6.2.2 Literature review (Task 1.2)

A literature review was undertaken covering three subtasks:

1. Check the dataset of basic characteristics and close gaps
   where possible using public information sources, such as
   other online databases, news articles, and reports;

2. Screen past or ongoing rehabilitation programmes that

3. Screen past or ongoing rehabilitation programmes that
   have taken place at the 87 stations; and

4. Review the key drivers and opportunities for hydropower

5. Review the key drivers and opportunities for hydropower
   modernisation using existing references.


In the review of past or ongoing modernisation programmes,
for stations where information was found, the year of the
rehabilitation was recorded, along with a note on what type
and scope of rehabilitation (e.g. electromechanical units,
electrical systems, or complete station rebuild for instance;
if this information was available). This review complemented
the data collection and owner surveys in activity 2 on the
rehabilitation status of plants.

The review of key drivers and opportunities for hydropower
modernisation was helpful in better understanding the
key factors that determine the need for modernisation,
with a particular focus on the African region. This helped
contribute primarily to section (Drivers and opportunities of
modernisation) and sections 6 & 10 (Summary of findings
and detailed assessment of candidate projects).

In parallel with the literature review, owners of the 87
stations were contacted to participate in the study. Contact
details were obtained through the combined IHA and AfDB
networks. In total, the 87 stations comprised 30 owners, who
were all sent a formal letter from IHA and AfDB explaining
the background of the study, together with an invitation to a
webinar which took place on 6 April 2022. The objective of
the webinar was for IHA to present the background context
of hydropower modernisation, the planned methodology
for the Continental Mapping Study and for AfDB to present

6.2.3 Webinar with owners (Task 1.3)

* * *

the AHMP. It was also an opportunity to invite the owners to
actively participate in the mapping process and encourage
participation in the data collection phase following the
webinar (activity 2). The invitations also effectively identified
the most relevant contact points at each organisation. During
the webinar, two live polls were taken on the key drivers and
barriers for hydropower modernisation, and questions from
participants on various parts of the agenda, as shown below:

What are the key drivers and opportunities for modernisation
projects?

What are the major barriers to hydro modernisation projects?

Low electricity
price / demand

Commercials
contract & permitting

The webinar was very well attended, with over 100
participants, including 75 from African hydropower
companies, representing two-thirds of the hydropower
companies invited. In addition to building engagement, the
webinar presentations and discussion points revealed several
key trends:

• Hydropower modernisation will be critical both globally
and in Africa

• Modernising hydropower plants goes beyond standard
refurbishments

• Initial mapping shows Africa has an ageing fleet and good
examples of projects that are suitable for modernisation
• New technology concepts have a key role to play in

• New technology concepts have a key role to play in
hydropower modernisation
• Access to financing is essential to move modernisation

• Access to financing is essential to move modernisation
projects forward
• Other matters discussed during the webinar included

06.3 \| Activity 2 – Station level
data collection and screening

The station-level template used to collect information
included a questionnaire and data form. Along with a
template Excel sheet prepared for each of the 87 stations.

Following the webinar and informed by the literature review
in Activity 1, Activity 2 focused on the collection of stationspecific data to assess the modernisation needs.

6.3.1 Station specific data collection (Task 2.1)

* * *

The form was divided into six sections:

↓

01

Modernisation history
aiming to gather information about any modernisation

aiming to gather information about any modernisation
activity that may have been undertaken in recent years, the
reasons and benefits, and any available information related to
the costs of modernisation.

↓

02

Current operating status
gathering insights on the current status of the asset, in terms

gathering insights on the current status of the asset, in terms
of operational power and annual generation compared to
installed capacity and optimal annual output; rate of forced
outages; if there are excessive spills (indicating the asset may
not be the right size relative to river flows, and/or occurrence
of flood events); recent condition assessments; and if there
are any major safety issues.

03

↓

Future modernisation plans

04

Annual performance data

05

if future modernisations are planned and information
on when, what type, the reasons and cost; if there are
any environmental or social legacy issues involved; and
request on any further details that may impact the station/
modernisation need.

10-year historical trends on annual powerhouse water
discharge (m3/s), annual operational capacity (MW), annual
generation (GWh) and capacity factor (%), annual availability
(%), planned & forced outage rate (days & %)

Floating solar assessment data

06

Further to the modernisation needs and performance of
the hydropower plants, data was requested to assess the
potential for floating solar PV at the hydropower reservoirs.
These data focused on both the overall characteristics of
the reservoirs (size, depth, level variation, wave height and
discharge) and the accessibility to the switchyard and the
capacity and the condition of the existing transmission line.

6.3.2 Engagement of owners in the data collection (Task 2.2)
The form then was sent to all owners covering the 87 stations in

The form then was sent to all owners covering the 87 stations in
scope, including a number who did not attend the webinar. The
response rates for the webinar in Task 1.3 and subsequent data
collection Task 2.2 phases are shown in Figure 16.

* * *

Figure 13. Response rates

6.3.3 Assessment of stations data (Task 2.3)

The assessment of the station data (Task 2.3, Figure 10) was
carried out in two steps:

• First, a qualitative judgement was made on each case
as to whether it was in high, medium or low need for
modernisation, based on general criteria presented in
Table 7 below.
• Subsequently, a quantitative assessment was then

• Subsequently, a quantitative assessment was then
carried out to score each plant's level of modernisation
need based on a set of specified criteria; this step was
undertaken on the 51 plants for which sufficiently detailed
information was received. The quantitative analysis was
done to validate the initial qualitative categorisations and
rank projects within each category.

Figure 14. Illustration of the two steps process used in the station
assessment (Task 2.3) criteria in an infographic

* * *

Step 01
Categorisation

Categorisation

In the first step, the data collected about the power plants
were reviewed and reorganised to extract a standardised set
of specific information enabling a comprehensive view of the
various plants.

Each plant’s modernisation needs were then categorised
between low, medium and high using a set of general criteria
summarised in Table 7. Plants were analysed across several
specific parameters extracted from the datasheets, i.e.
on modernisation history, current operating status, future
modernisation plans, and the annual performance of the
plants.

Table 07. General criteria guiding the stations’ categorisation

Criteria used for plants lacking data

| Low need | Medium need | High need |
| --- | --- | --- |
| Performances |  |  |
| Good - high availability, low forced outage rate | Satisfactory - some years with low availability and evidence of forced outage rate | Poor - low availability, high forced outage rate over extended period |

| Owner outlined not in need of modernisation | Partial modernisation completed or underway | Key components reaching end of life and no recent modernisation completed |
| --- | --- | --- |
| Full works completed or underway | Minor works required/scheduled | Owner or government outlined priority for modernisation or expansion |
| Modernisation to commence shortly- contracts already in place | - | Modernisation plans in place,sometimes pending a complete feasibility study |

Components condition & modernisation status

Plants with good performance or modernisation projects
recently completed, underway or commencing shortly were
classified as low need.

Conversely, plants running outdated technology79, with poor
performances due to low availability, high forced outage,
and/or indication of derated or compromised units were
typically classified as high need. Often this judgment was
facilitated by some clear indications provided by the owners
about one or multiple plants in their fleet requiring imminent
modernisation works for which an initial assessment was
already carried out.

Finally, hydropower plants relying on units that were not
recently installed but still operating reliably, possibly thanks
to a good maintenance programme or small rehabilitation
works carried out over time, were classified under the
medium need category.

Step 02
Scoring process

For example, on the age of the major electromechanical
equipment, a plant with generating units older than 45 years
since the last refurbishment was assigned a score of 2, those
with units between 31-45 years old scored 1, while those

Scoring process

As illustrated in Figure 14, besides the qualitative assessment
(step 1), in the second step of the process, a quantitative
assessment was done to assign a score describing the
rehabilitation needs of each station. This more quantitative
analysis aimed to corroborate the results of the above
qualitative categorisation process. Leveraging the data
received by the owner, a modernisation need score was
calculated for the candidate plants owned by companies that
provided sufficient information. The modernisation score was
calculated as the sum of individual points associated with
some specific criteria describing the condition of the power
plant.

* * *

under 30 scored 0. These age boundaries correspond to
typical ageing rates of hydro turbine generators, as found in
the literature review of modernisation drivers and benefits
(see section 4). Other main assessment criteria were also
scored, e.g. Is the owner indicating major mechanical issues?
(Yes scored 1, whereas No scored 0); Is the owner indicating
a need for civil works?; Is a share of the installed capacity out
of service?; Is annual generation below expectations?, etc.

All scoring criteria used in calculating the total modernisation
need a score for the 51 plants are shown below in Table 8.

Table 08. Criteria used in the scoring process of stations’
modernisation needs

| Scoring criteria for hydropower modernisation needs |
| --- |
| How old is the electromechanical equipment? (0-30y=0, 31-45y=1, 45y+=2) |
| Is owner indicating major mechanical issues? (Y=1,N=0) |
| Is owner mentioning need for Civil works? (Y=1,N=0) |
| Is there power out of service relative to installed MW capacity? (0%=0,1-50%=1,＞50%=2) |
| Is annual generation in 2020 and 2021 below expectations? (0-50%=2,50%-90%=1,＞90%=0) |
| Has the owner linked low generation to water level issues? (Y=-1,N=0) |
| Has the owner linked low generation to low grid demand? (Y=-1,N=0) |
| Has annual availability in 2020 and 2021 been low? (<80%=2,80%-90%=1＞90%=0) |
| Indication of high forced outages? (Y=1,N=0) |

| Has the owner plans or indications for modernisation? (Y=1,N=0) |
| --- |
| Has the plant a substantial role on the grid? (>10% national supply=1,<10%=0) |
| Has the owner indicated safety issues? (Y=1,N=0) |

Is there indication of excessive spills? (Y=1, N=0)

Summing the resulting values associated with each criterion
gave a total score for each station out of a maximum of
15\. These results were used to validate the qualitative
categorisations and prioritise candidates most needing
modernisation. In some cases, specific data fields were
missing in the responses from owners, reducing the total
score possible for those stations.

Floating solar assessment
The main criteria for assessment of sites’ potential for

Floating solar assessment
The main criteria for assessment of sites’ potential for
floating solar were as follows, based on a screening
methodology and literature review of constraints for floating
PV at hydropower reservoirs:

Solar irradiance in the reservoir area
in order to assess the level of resource availability

↓

Reservoir geometry (surface area and water
depth) and water level variations
to assess the space availability for floating solar PV and

to assess the space availability for floating solar PV and
constraints on the anchoring and mooring floating structure.
Further bathymetric surveys would be required in a feasibility
study.

* * *

Transmission line utilisation factor and
excess capacity

to understand if there is available grid connection capacity at
the existing site to evacuate power from the floating PV, and
the hydropower facility’s generation.

Distance between the reservoir and the
switchyard

affects the cable connection cost.

Reservoir uses

to assess constraints if the reservoir is used for other
purposes beyond water storage for energy production.

on maximum wave height, transformer capacity, reservoir
discharge ratio, turbine ramping rate – which could further
affect suitability for floating PV and hybrid operations.

Scoring criteria for hydropower modernisation needs

How large is the hydro plant capacity? (0-49MW=0, >50MW=1)

Is solar irradiation intensity at the site above 2000 kWh/m2/year? (Y=1, N=0)\*

In total, data was received for 26 hydro reservoir sites from
owners for the floating solar assessment. A scoring process
was also used to screen the dataset against the criteria
specified in Table 09.

Is the reservoir surface area above 4000 m2? (Y=1, N=0)

Is the maximum reservoir depth below 50m? (Y=1, N=0)

Are the maximum water level variations below 25m? (Y=1, N=0)

Is the reservoir single purpose, for energy production only? (Y=1, N=0)

Is the maximum wave height below 2m? (Y=1, N=0)

Is the distance between the reservoir and switchyard below 3km? (Y=1, N=0)

Is there spare transmission capacity available (above 30MW)? (Y=1, N=0)

\*NOTE
solar irradiation data was available from a public database per location (globalsolaratlas.info)

Is the turbine type flexible? (Pelton/ Francis=1, otherwise=0)

\*NOTE
solar irradiation data was available from a public database per location (globalsolaratlas.info)

Total score

A selection of candidate sites was then reviewed in more
detail, discussing the various site characteristics and
potential constraints according to those screened in Table
9\. The potential energy yield from a 50 MW floating solar
array was also calculated based on a methodology from
a published EU JRC study80. FPV yield is calculated by
multiplying various input terms and assumptions. These
include solar irradiation at the site (kWh/m2/y), % of
reservoir surface area covered by FPV (i.e. km2 covered),

Each station could receive a maximum possible score of
10 (1 point per listed criteria). The total scores were used
to rank the hydro sites regarding suitability for floating PV.
Note some of the datasheets had missing data fields which
reduced the overall score possible for those cases.

* * *

PV area factor (assumed as 0.1 kW/m2), PV performance
ratio accounting for system losses & cooling effects (0.8
assumed), and AC/DC inverter load ratio (1.25 assumed
including solar clipping).

06.4 \| Activity 3 – detailed
assessment

Hydropower stations assessed in high need of modernisation
in Activity 2 were carried forward as shortlisted candidates
into Activity 3. In this project phase, a more detailed analysis
was carried out to understand better the context and the
required rehabilitation work for each case.

6.4.1 Detailed assessment of stations with high needs
(Task 3.1)

• Annual performance indicators (historical generation
and availability trends)
• Operational issues (further detail on ongoing equipment

it could improve after the modernisation (contribution
to total national supply; baseload or peaking services;
generation profile concerning seasonal hydrological
flows; reservoir storage; cascade operations with other
plants)
• Annual performance indicators (historical generation

• Scope of potential modernisation (components and
works required; status of the project regarding timeline,
studies, funding secured; the magnitude of energy gains
from a modernisation, if available)
• Cost estimates of modernisation (either provided

• Hydropower station overview and description (key
essential characteristics; categorisation rationale; age
& condition of electromechanical units; year of last
refurbishment; key modernisation needs – no. of units
impacted and if any civil works would be required)

• Cost estimates of modernisation (either provided
directly by the owner where possible and/or using IHA
benchmark ranges applied to the capacity impacted)
and owners preferred legal structure for modernisation
(public, Independent Power Producer or Public Private
Partnership)
• Potential for solar PV (with any additional detail on

• Potential for solar PV (with any additional detail on
project constraints, the status of studies)
• Further considerations (e.g. sediment management,

6.4.2 Dissemination and presentation of results (Task 3.2)

The final task of the project focuses on disseminating
and presenting the results. This is mostly covered by the
preparation of this report and the participation at several
events and webinars to showcase the high-level findings of
this work.

06.5 \| Environmental &
sustainability

As part of the screening activities focusing on assessing the
hydropower plant conditions, IHA has attempted to collect
information regarding the environmental and sustainability
(E&S) impacts of modernisation projects for the plants in
the high-need category. However, insufficient information
was available at this stage, and further assessment would be
needed on a project-by-project basis ahead of modernisation
work. IHA has prepared a review of the possible E&S
impacts of the modernisation works required by the highneed stations. This was prepared in consultation with the
IHA Sustainability Team, and it also includes some general
suggestions about Good International Industry Practice
(GIIP) to be followed in preparation for rehabilitation and
modernisation projects. The results of this review are
presented in section 08.

* * *

Section 07
Summary of findings

This section presents the results of the mapping exercise
carried out by IHA by following the methodology described
in section 06.

07.1 \| Continent-wide mapping
and regional analysis

The findings of the station-level assessments obtained
applying the methodology described in sections 6.3.3 and
6.4 for the 87 hydropower plants totalling 24,200 MW across
Africa are presented in Figure 18. This shows the number
of plants assessed to be in high, medium and low need for
modernisation at the regional level, with the results shown in
Table 10 alongside the installed capacity in each category.

North Africa

Number of plants assessed

West Africa

High need Medium need Low need

* * *

Table 10. Regional overview of modernisation needs by number of
stations and installed capacity

|  | Low need |  | Medium need |  | High need |  |
| --- | --- | --- | --- | --- | --- | --- |
| Region | No. stations | Capacity(MW) | No. stations | Capacity(MW) | No. stations | Capacity(MW) |
| North Africa | 0 | 0 | 7 | 3,094 | 0 | 0 |
| West Africa | 3 | 1,268 | 3 | 430 | 4 | 2,103 |
| East Africa | 6 | 538 | 6 | 938 | 7 | 625 |
| Central Africa | 5 | 923 | 5 | 666 | 3 | 1,557 |
| Southern Africa | 16 | 6,800 | 15 | 4,961 | 7 | 337 |
| TOTALS | 30 | 9,529 | 36 | 10,089 | 21 | 4,621 |

Overall, 21 plants totalling 4,621 MW – approximately 20% of
capacity screened and representing 12% of the total African
fleet – were assessed with high modernisation needs; 36
plants equivalent to 10,089 MW (approx. 40% capacity
screened) in medium need; and 30 plants totalling 9,529
MW (approx. 40%) were categorised as low need. East and
Southern Africa had the highest number of plants with
high needs, whereas West and Central Africa had the most

Overall, 21 plants totalling 4,621 MW – approximately 20% of
capacity screened and representing 12% of the total African
fleet – were assessed with high modernisation needs; 36
plants equivalent to 10,089 MW (approx. 40% capacity
screened) in medium need; and 30 plants totalling 9,529
MW (approx. 40%) were categorised as low need. East and
Southern Africa had the highest number of plants with
high needs, whereas West and Central Africa had the most

significant amount in high demand for installed capacity.

Table 11. Archetype cases and characteristics of plants classified as
high, med or low need

Plants recently built or refurbished/ upgraded (0-30 years), operate at or near design performance levels and do
not report any particular electrical, mechanical or civil issues.

\*For those plants lacking data, rehabilitations noted as completed or well progressed, and no indication of urgent
issues.

Plants are running old technologies but not experiencing major mechanical problems limiting their production.

Plants partially compromised and running at somewhat reduced capacity because of a specific electrical,
mechanical or civil issue, regardless of age.

Medium need

\*For those plants lacking data, rehabilitation plans & projects reported due to their age and/or partial rehabilitations
undertaken; but the current status is unclear.

Plants running old technology (30y +) and are currently experiencing repetitive outages or mechanical issues
limiting their productivity (e.g. unit(s) out of service, safety issues, repetitive forced outages).

Plants severely compromised with several (or all) units out of service and/ or incapable of producing at all,
regardless of their age.

\*For those plants lacking data, reports identified poor condition due to age and urgent needs for rehabilitation &
repairs indicated; many with committed projects.

Figure 16 illustrates the percentage of stations identified
as high needs requiring modernisation, categorised by the
components of the asset; showing that 54% of the assets
necessary modernisation primarily to the electro-mechanical
systems (stators, rotors, turbines, etc.), whereas the
remaining 46% required work on both the electro-mechanical
systems and civil structures.

* * *

Figure 16. Percentage split of the number of high need cases
depending on the type of work required

Figure 17 maps the stations according to age of
electromechanical equipment since last major refurbishment
(along the X axis, in years) and annual generation/expected
generation (along the Y axis, in %). The size of the bubble
reflects the size of the installed capacity (MW) of the plant.

• in some specific cases, sedimentation was a major driver
of the need for modernisation

• cooling systems malfunctioning
• lack of spare parts, which often triggers cannibalisation

Most stations that were categorised as high need exhibited a
range of recurrent problems, which in some cases resulted in
derating the plant's design capacity. These issues included:

• high shaft vibration when operating at rated power,
• high temperature in a turbine thrust bearing

• high temperature in a turbine thrust bearing
• cooling systems malfunctioning

The colour indicates if it was classified as low (green),
medium (yellow) or high (red) modernisation need.

Figure 17. Mapping of stations by key assessment criteria

units of different age the weighted average of the age of the units is considered.
Bubble size: Representing the size of the installed capacity (MW).

* * *

Those assessed in low need (blue) showed relatively lower
age of equipment (<20 years) and recent annual generation
closer to optimal (100%). In contrast, the medium (in yellow)
and high need (red) cases were more distributed across
the chart. Most showed reduced generation, around or
below 65% of expected output, and/or electromechanical
components over 30 years old since commissioning or
the last major refurbishment. A few outliers with units
under 30 years old reported specific ongoing equipment
or performance issues. Some data points also sit along the
bottom axis at 0% generation, as these plants have been shut
down due to aged and damaged equipment.

7. 2 \| Quantitative assessment

7.2.1 Ranked list of candidates

The plants were scored against specific criteria using
performance indicators and feedback received in the
datasheets, as outlined in the methodology. The results of
this quantitative assessment confirmed the high-need cases
identified in the initial categorisation of plants into high,
medium and low-need groups based on qualitative reviews
and further provided a ranking of the candidate stations.
In summary, the high need cases scored in the 6.5 – 12 range
out of a maximum of 15 across the assessment criteria;
medium cases scored 2.5 – 5.5; and low need cases scored
0 – 2.5.

07.3 \| Cost estimates for
modernisation projects in Africa

Additional information was gathered on costs in Africa
based on estimates provided by owners and secondary
sources. Most of the cost estimates were for the proposed
rehabilitation and replacement of electromechanical
components; The data collected for each project
included installed capacity associated, cost estimate for
modernisation, the reference year for the estimate received,
and the 2020 actualised cost following the world-level
benchmarks methodology, US$/MW calculation.

The statistical distribution of these US$/MW cost estimates
was then calculated and compared with the distribution of
the IHA world-level benchmark values, as shown in Table 12.

Table 12. Comparison of IHA benchmarks with African modernisation
cost estimates (electromechanical installations)

|  | IHA Benchmark | African Estimates |
| --- | --- | --- |
|  | US$/MW | US$/MW |
| Min | 90,988 | 227,132 |
| Q1 | 290,923 | 317,950 |
| Median | 431,852 | 413,514 |
| Q3 | 542,175 | 514,551 |
| Max | 945,427 | 622,277 |
| Mean | 463,815 | 417,898 |

* * *

In general, the datasets correlate reasonably, and particularly
when looking at the median and mean values which are in
the same ballpark, in the US$400,000-500,000/MW range.

7. 4 \| Overall investment needs

An estimation was also made of the total investment
needs of installed capacity assessed in high and medium
needs in the mapping study. For this calculation, IHA’s

An estimation was also made of the total investment
needs of installed capacity assessed in high and medium
needs in the mapping study. For this calculation, IHA’s

needs in the mapping study. For this calculation, IHA’s
benchmark cost was assumed to cover the modernisation of
electromechanical components (mean value: US$464,000/

electromechanical components (mean value: US$464,000/
81
MW), multiplied by the capacity in each category, with
results shown in Table 13.

electromechanical components (mean value: US$464,000/
, multiplied by the capacity in each category, with

Table 13. Overall estimates of investment need for total capacity
assessed in the study with high and medium needs for modernisation

|  | High need | Medium need |
| --- | --- | --- |
| Installed capacity assessed in in the mapping† | 4.6GW | 10.1GW |
| % of overall African hydropower fleet in 2021(38.5GW)^{82}$ | 12% | 26% |
| Estimated investment need based IHA benchmark modernisation cost^{††}$ | Approx.US$2.1 billion | Approx.US$4.7 billion |
| Indicative capacity upgrade associated with complete modernisation project^{83}$ | 0.23GW-0.53GW | 0.51GW-1.17GW |

† This total includes power plants for which data were received directly from the owners and plants for which only secondary
data were available.
†† The estimated investment figures in the table are exclusively aimed at providing an indication of the order of magnitude of the

The results from this level of investment would be extremely
beneficial to the economic and social development of the
continent. A comprehensive hydropower plant modernisation
programme would secure over 14.7 GW of reliable
electricity generation, increase plant flexibility, improve the

data were available.
†† The estimated investment figures in the table are exclusively aimed at providing an indication of the order of magnitude of the
investment required and should be taken as a general indication only.

existing fleet's health and safety operations and boost the
actual generation. According to a research paper on the
modernisation of hydropower plants published in 2021, the
replacement of ageing turbines has the potential to increase
system efficiency between 4% and 6% and the installed
84
capacity between 5% and 11.6%. This translates into a total
potential capacity gain between 740 MW and 1.700 MW for
85
the 14.7 GW in high and medium need.

7. 5 \| Floating solar assessment

7.5.1 Screening of candidates
Data was gathered for 26 hydro reservoir sites to assess

Data was gathered for 26 hydro reservoir sites to assess
potential suitability for FPV. Based on the methodology
outlined in section 06, the list of sites was scored against a
range of screening criteria, receiving a score out of 10 per
site, with higher scores indicating higher potential suitability.
The screening exercise resulted in a total of 11 candidate
sites based on acceptable scores (indicating better likelihood
of site suitability), geographic spread (max three sites per
country) and completeness of data received.

Reviewing the 11 hydro reservoir sites, the characteristics that
were used to select these sites were as follows:

• Solar irradiance was generally higher than the 2000
kWh/m2/y average for the African continent for most
candidate sites (referenced in a European Commission
86
Joint Research Centre (JRC) study).
• Reservoir surface area was more significant than 1 km2 in

• Reservoir water level variations for several sites
exceeded the scoring threshold of 25 m max, another
factor impacting anchoring and mooring.

* * *

• Seven reservoirs were single-purpose, suggesting a
low likelihood of other reservoirs restricting the use
of floating panels. However, most of the multipurpose
functions were for flood control and irrigation, which
would not necessarily impact use of the floating panels.
• Max wave heights were generally below 1 m, which poses

• Max wave heights were generally below 1 m, which poses
no particular constraint.

• Distance between reservoir and switchyard was below
3 km for most sites. Longer distance would add cabling
cost to connect in the floating PV system but would not
necessarily preclude projects. In some cases, other tie-in
points may also exist nearer the reservoir sites.
• Some extent of spare transmission capacity at the

• Some extent of spare transmission capacity at the
hydropower stations’ grid connection was identified
for all the listed cases. Most of the 9 cases suggested
at least 30-50 MW available, based on reported excess
transmission capacity available (in MW), or line utilisation
factor (in %), which is lower than 100% suggests
spare headroom. There may also be cases where solar
generation could enable hydro generation to be reduced
during those periods, which may benefit operators in
preserving water levels at the reservoir. These aspects
would need detailed study and power system studies to
assess the capability of the local grid to handle added
solar power supply. Capacity constraints would also
affect FPV system sizing.
• The last criterion showed most of the hydro stations had

7.5.2 Solar energy yield calculation

assumptions. These include solar irradiation at the site
(kWh/m2/y), % of reservoir surface area covered by FPV (i.e.
km2 covered), PV area factor (assumed as 0.1 kW/m2), PV
performance ratio accounting for system losses & cooling
effects (0.8 assumed), and AC/DC inverter load ratio (1.25
assumed including solar clipping).

To represent the potential solar energy yield, annual output
from a proposed FPV system was calculated based on
various input assumptions; and by comparing the increase in
generation achieved at selected hydro sites.

• The last criterion showed most of the hydro stations had
Francis turbines which would provide more ramping
flexibility to accommodate solar output fluctuations.

To review a reasonable scenario, the calculation assumed a
500,000 m2 surface area of reservoir covered by FPV, i.e. a
50 MW system size, which gave a % area covered depending
on the reservoir size in each case.

Annual FPV output is in the 100-125 GWh range from the 50
MW system assumed.

The study shows that floating solar hybrids could be a
valuable means of improving generation at hydro sites during
drought events. They also provide a quick win, given their
relatively short deployment timescales.

* * *

Section 08
E&S sustainability review of
high need plants

0 8.1 \| Introduction

To collect data about the possible E&S implication associated
with the modernisation need of the plants in high demand,
simplified questionnaires were sent to the plant owners
based on the standard's performance requirements and
technical criteria. From the results of the questionnaires, it
was hoped to provide a detailed E&S review of the potential
impacts of the different modernisation projects.
Unfortunately, there have been no responses to date.
Nonetheless, the following section presents a literature
review and desk-based analysis of similar examples of
modernisation projects to highlight key trends and flag any
high-risk areas.

08.2 \| Work required by the
high need cases and highlevel considerations on the E&S
impacts

A high-level summary of the work needed by each of
the plants identified in high need is summarised into the
following categories:

• electromechanical systems;
• minor civil infrastructure work;

• minor civil infrastructure work;
• reconstruction of transmission infrastructure;

• reconstruction of transmission infrastructure;
• sedimentation removal;

• modernisation involving an increase in capacity.

• sedimentation removal;

The scope of identified high need stations is almost always
exclusively focused on the modernisation of the electrical
and electromechanical equipment of the plant. These
typically include drivetrain components (i.e., generator,
turbines, stators and rotors), control structures (i.e., gates,
valves and cranes), transformers, high voltage switchgear,
auxiliary electrical services, and electrical control systems.
In a few cases, interventions on the civil structure are
required. Still, these always aim to maintain the current
infrastructure (housing, water intake and outlet, and dam) in
a safe and reliable operating status rather than expanding the
dam size.

* * *

They may even be positive in some instances.

Indeed, the scope of a modernisation project is often
to rehabilitate the power plant to its original nameplate
condition, which usually implies a better utilisation of
water resources due to higher efficiency and enhanced
unit regulating capacity, as well as more efficient and safer
operations. Rehabilitated plants require less extraordinary
maintenance and are often a safer working environment.
Additionally, the introduction of modern and more efficient
electromechanical equipment can, in specific cases, enable
the plant to extend its operating range and may result
in a reduction in start & stop operations, allowing better
regulation of the water discharged from the plant and the
maintenance of a minimum water level in the downstream
river during the period of low water availability. Rehabilitation
and modernisation projects can also be associated with
implementing other measures aimed at mitigating the
original project's possible negative impacts. These measures
include improved fish passage by introducing fish ladders or
improved turbine seals, which eliminate lubricant leakage.
In general, one of the main aspects to be considered is
the alteration or the diversion of the water flow passing
through the power plants during the period of the works.
This aspect has biological implications, due to the possible
change in water supply in the downstream river, as well as
social impacts, due to the possible utilisation of the water
87
released by the plant for other activities. It is generally
recommended to rehabilitate hydropower power plants
equipped with multiple units adopting a multi-stage
approach with work being carried out sequentially on the
various units. This approach will limit the overall impact of
the results on the electricity production and water supply to
the downstream river.

Although this is not the case for any of the plants reviewed in
detail, it is essential to underline that if the work should also
require an expansion of the dam, this will need a detailed
assessment of the physical, biological and social implications
associated with the additional upstream area impounded
by the reservoir and the erection of the new civil structures.
These cases are almost comparable to a greenfield project,
as the major civil engineering interventions will substantially
alter the E&S impact of the installation.

Finally, particular attention should be dedicated to projects
for power plants located in World Heritage sites or with preexisting conflicts with local communities. This may generate
potential constraints on the extraction of additional water for
88
electricity production as well as the accessibility of the site.

The IHA has cooperated with various relevant stakeholders,
including environmental & social NGOs, governments,
operators, suppliers, and financial institutions, in preparing
the Hydropower Sustainability Standard. This is a global
certification scheme specifically designed for greenfields
88
and brownfields hydropower projects. The Standard is
aligned with green finance initiatives such as the Climate
Bonds Initiative’s Hydropower Criteria, and is often required
to access green finance.

* * *

Section 09
Conclusion and
recommendations

0 9.1 \| Mapping conclusions

Modernisation has a variety of drivers and potential
improvements, which are determined by the conditions
and options available for an individual site. Modernisation
projects provide an opportunity to address legacy issues
of older stations while offering a window to implement
up-to-date energy technologies, capacity upgrades, and
environmental measures at existing sites at relatively low
cost. In countries with ambitious decarbonisation plans,
modernising hydropower using technologies to enhance
flexibility services will help support growth in variable
renewables coming onto the system. Several case studies
illustrated the approaches and benefits that can be achieved.

Moreover, the need for modernisation has never been
more important. IEA’s Special Hydropower Market Report
2021 forecasts that globally, around 45% (170 GW) of the
projected increase in hydropower capacity by 2030 will
derive from existing infrastructure; the forecast considers
projected growth in the range of 4-5 GW from replacements
and uprates of the existing fleet in Africa and the Middle
East (primarily Sub-Saharan Africa). In all growth scenarios,
adequate investment into today’s hydropower capacity
will be essential to sustain and enhance reliable electricity
supplies for decades.

Out of the 24.2 GW of installed hydropower capacity
covered in the study, 4.6 GW was assessed in high need
of modernisation, making up over 10% of Africa’s overall
hydropower fleet and representing an estimated US$2.1
89
billion of required investment. For the most part, the 21
high-need plants identified in the mapping were using
old technology and experiencing frequent outages or
mechanical issues limiting productivity, with generating units
often working at limited power or completely out of service.
This level of investment would not only restore roughly 800
MW of existing hydropower capacity currently out of out of
service. Still, it could potentially increase up to 11% of these
plants' overall installed nominal capacity.

A further 10.1 GW was assessed in medium need of
modernisation, covering a further 25% of the Africa’s total
installed hydropower, and representing an additional US$4.7
billion of estimated investment required. The 36 plants
categorised in medium need, while not experiencing such
major problems as the high need cases, were nonetheless
running old technologies and in many cases partially
compromised and are likely to require investment in
rehabilitation or upgrading of facilities in the coming years.
Regionally, all plants identified in high need of modernisation
were in Sub-Saharan Africa. In terms of installed capacity,
just over 90% was located across West (2.1 GW), Central (1.6
GW) and East Africa (0.6 GW), with the remainder in Southern
Africa (0.3 GW). All regions had additional capacity in medium need, particularly Southern Africa (5 GW) and North
Africa (3 GW).

All these plants need extensive modernisation work to
restore existing electromechanical infrastructure to full
capability and improve annual production and performance
by installing new, more efficient technologies. There are
also opportunities to increase capacity through upgrades
or expansions and/or by installing floating (or land-based)
solar PV at or near the hydropower site. Each case would also
support progress in decarbonisation and interconnection
of grids by improving the availability and reliability of clean
electricity supply. Additionally, the modernisations would
provide a chance to adapt existing hydropower to be more
resilient against climate change impacts, particularly in
those countries experiencing hydrological variability. These
projects are also likely to be cost-effective options compared
to greenfield alternatives.

From an environmental & social perspective, rehabilitation
works to increase efficiencies, replace equipment, and rectify
ageing infrastructure issues could be considered usual asset
management practice for operations and normally would not
instigate a change in the project's impacts. These projects
are often an excellent opportunity to implement measures
that can improve the E&S footprint of the plant and its
operations. Examples of these measures are the introduction
of fish ladders or improved turbine seals, which eliminate
lubricant leakage.

The mapping has recommended a list of plants categorised
in high or medium need, some of which would require
further investigation to better understand the current status
and specific investment needs. The study has also set out
a shortlist of priority candidates for the AfDB to consider
for modernisation and investment – with assessments and
summaries compiled for these cases in collaboration with the
plant owners.

Recommended next steps would be to investigate further the
investment needs and scope of works and conduct feasibility
for selected projects – also considering any potential
additional barriers (e.g. financing or environmental &
sustainability (E&S)) as well as other opportunities that could
be included in a proposed modernisation (drawing on the
drivers & opportunities outlined in Chapter 3, and any further
E&S benefits identified). This would involve working closely
with the owners, relevant specialists, and suppliers.

More specifically, for those stations identified as in high need
of modernisation, it is recommended that a more detailed
analysis be undertaken to optimise the investment needs for
the facility. For those stations identified as medium needs,
a comprehensive monitoring program is recommended
to assess the condition and performance of the asset on a
cyclical basis.

* * *

References

1 [www.iea.org/reports/africa-energy-outlook-2019](http://www.iea.org/reports/africa-energy-outlook-2019).
iea.blob.core.windows.net/assets/2f7b6170-d616-4dd7-a7caa65a3a332fc1/Africa\_Energy\_Outlook\_2019.pdf
2 [www.iea.org/fuels-and-technologies/electricity](http://www.iea.org/fuels-and-technologies/electricity)
3 IHA hydropower database.

3 IHA hydropower database.
4 [www.iea.org/regions/africa](http://www.iea.org/regions/africa) and IEA Africa Energy Outlook 2022.
5 Source: IEA, World Energy Outlook-2021. Access to electricity.
6 The total power of the African hydropower fleet is taken from
the IHA Status report 2022: [https://www.hydropower.org/](https://www.hydropower.org/)
publications/2022-hydropower-status-report

publications/2022-hydropower-status-report
7 This figure is based on a study focused on the European fleet,
indicating achievable power increase between 5% and 11.6% when
replacing old, deteriorated turbines based on outdated technology.
“Assessing the energy potential of modernizing the European
hydropower fleet”, Emanuele Quaranta and others, 2021. [https://doi](https://doi/).
org/10.1016/j.enconman.2021.114655
8 Total installed costs for green field hydropower projects are

8 Total installed costs for green field hydropower projects are
generally in the range of 2,100 US$/kW (IRENA 2021 Renewable
Power Generation Costs), while modernisation project costs are in
the range of 400-500 US$/kW. Additional information about the
modernisation cost benchmark is available in Section 5.
9 A list of the top 5 FPV projects in 2025 is available in the following
article:
[www.ysgsolar.com/blog/5-largest-floating-solar-farms-world-2022-](http://www.ysgsolar.com/blog/5-largest-floating-solar-farms-world-2022-)

article:
[www.ysgsolar.com/blog/5-largest-floating-solar-farms-world-2022-](http://www.ysgsolar.com/blog/5-largest-floating-solar-farms-world-2022-)
ysg-solar
10

documents.worldbank.org/curated/en/518271468336607781/
Rehabilitation-of-hydropower-an-introduction-to-economic-andtechnical-issues (accessed 3 December, 2019).
14 Martins Nogueira, M. and Alarcón, A., 2019. ‘Impacto de las

14 Martins Nogueira, M. and Alarcón, A., 2019. ‘Impacto de las
paradas en la generación hidroeléctrica de Brasil’. Nota técnica del
BID; IDB-TN-01595.
15 (accessed 2 December, 2019).

15 (accessed 2 December, 2019).
16 [www.advantageaustria.org/us/events/Andritz-Hydro.pdf](http://www.advantageaustria.org/us/events/Andritz-Hydro.pdf)
17 [www.hydropower.org/sediment-management](http://www.hydropower.org/sediment-management)
18 [www.osti.gov/etdeweb/servlets/purl/21397677](http://www.osti.gov/etdeweb/servlets/purl/21397677)

18 [www.osti.gov/etdeweb/servlets/purl/21397677](http://www.osti.gov/etdeweb/servlets/purl/21397677)

22 [www.andritz.com/resource/](http://www.andritz.com/resource/)
blob/31840/5cab6294379100be61fdd75aa590769f/hydro-servicerehab-en-data.pdf (accessed 25 November, 2019).
23 [www.ge.com/reports/tiny-bubbles-big-impact-hydro-power-plant-](http://www.ge.com/reports/tiny-bubbles-big-impact-hydro-power-plant-)

23 [www.ge.com/reports/tiny-bubbles-big-impact-hydro-power-planthelp-save-north-carolina-lake/](http://www.ge.com/reports/tiny-bubbles-big-impact-hydro-power-planthelp-save-north-carolina-lake/)
24 [www.nww.usace.army.mil/Media/News-Releases/](http://www.nww.usace.army.mil/Media/News-Releases/)

help-save-north-carolina-lake/
24 [www.nww.usace.army.mil/Media/News-Releases/](http://www.nww.usace.army.mil/Media/News-Releases/)
Article/1473327/18-026-corps-of-engineers-awards-321-millionmodernization-contract-to-design-m/
25 [www.ge.com/reports/go-with-the-flow-these-engineers-are-](http://www.ge.com/reports/go-with-the-flow-these-engineers-are-)

25 [www.ge.com/reports/go-with-the-flow-these-engineers-arebuilding-a-fish-friendly-hydropower-plant/](http://www.ge.com/reports/go-with-the-flow-these-engineers-arebuilding-a-fish-friendly-hydropower-plant/)
26 Marx, P., 2019. ‘Leverage existing hydropower assets to support

building-a-fish-friendly-hydropower-plant/
26 Marx, P., 2019. ‘Leverage existing hydropower assets to support
the energy transition’. GE Renewable Energy presentation, World
Hydropower Congress 2019
27 Compared to green field project.
28 For instance, the Kariba South power station located on the

28 For instance, the Kariba South power station located on the
Zambezi River was modernised in 2010 and the capacity of the
four Francis units was increased 150 MW to 180MW. This provided
total power uplift of 120 MW. [https://www.nsenergybusiness.com/](https://www.nsenergybusiness.com/)
projects/kariba-north-hydroelectric-power-station/
29 [www.hydroreview.com/world-regions/refurbishment-renewing-](http://www.hydroreview.com/world-regions/refurbishment-renewing-)

29 [www.hydroreview.com/world-regions/refurbishment-renewingveteran-assets-and-securing-new-megawatts-in-zambia-andnicaragua/#gref](http://www.hydroreview.com/world-regions/refurbishment-renewingveteran-assets-and-securing-new-megawatts-in-zambia-andnicaragua/#gref)
30

30 [www.hydropower.org/sediment-management-case-studies/sudanroseires](http://www.hydropower.org/sediment-management-case-studies/sudanroseires)
31 ecdpm.org/work/african-power-pools-regional-energy-nationalpower
32 ecdpm.org/application/files/1816/6074/5141/DP-244-African-

32 ecdpm.org/application/files/1816/6074/5141/DP-244-African-
Power-Pools-1.pdf
33 [www.grida.no/resources/5184](http://www.grida.no/resources/5184)
34

33 [www.grida.no/resources/5184](http://www.grida.no/resources/5184)
34 techcentral.co.za/for-the-first-time-there-is-real-concern-aboutthe-stability-of-the-grid/204566/
35 [www.hydroreview.com/hydro-industry-news/voith-hydro-](http://www.hydroreview.com/hydro-industry-news/voith-hydro-)

the-stability-of-the-grid/204566/
35 [www.hydroreview.com/hydro-industry-news/voith-hydrocompletes-modernization-work-on-1000-mw-drakensberg-pumpedstorage/#gref](http://www.hydroreview.com/hydro-industry-news/voith-hydrocompletes-modernization-work-on-1000-mw-drakensberg-pumpedstorage/#gref)
36 [www.engineeringnews.co.za/article/sapp-to-prioritise-malawi-](http://www.engineeringnews.co.za/article/sapp-to-prioritise-malawi-)

power
39documents1.worldbank.org/curated/en/184131524133396228/pdf/
Project-Information-Document-Integrated-Safeguards-Data-Sheet-
AFCC2-RI-3A-Tanzania-Zambia-Transmission-Interconnector-P163752.
pdf
40

41 [www.esi-africa.com/industry-sectors/transmission-anddistribution/wapp-north-core-project-for-interconnectivity-to-becompleted-in-2023/](http://www.esi-africa.com/industry-sectors/transmission-anddistribution/wapp-north-core-project-for-interconnectivity-to-becompleted-in-2023/)
42 [www.andritz.com/hydro-en/hydronews/hydropower-africa/](http://www.andritz.com/hydro-en/hydronews/hydropower-africa/)

43 [www.hydroworld.com/articles/2017/06/epri-releases-whitepaperon-hydro-plant-operations.html#gref](http://www.hydroworld.com/articles/2017/06/epri-releases-whitepaperon-hydro-plant-operations.html#gref)
44 Frankl, P., 2019. ‘The need for modernizing hydro in rapidly
changing power systems’. IEA presentation, World Hydropower

37 [www.esi-africa.com/industry-sectors/business-and-markets/](http://www.esi-africa.com/industry-sectors/business-and-markets/)
special-offer-sapp-mapped-out-to-showcase-opportunities/
38 ecdpm.org/work/african-power-pools-regional-energy-nationalpower

36 [www.engineeringnews.co.za/article/sapp-to-prioritise-malawitanzania-angola-for-regional-grid-integration-2018-11-28](http://www.engineeringnews.co.za/article/sapp-to-prioritise-malawitanzania-angola-for-regional-grid-integration-2018-11-28)
37 [www.esi-africa.com/industry-sectors/business-and-markets/](http://www.esi-africa.com/industry-sectors/business-and-markets/)
special-offer-sapp-mapped-out-to-showcase-opportunities/

html
69 [www.addleshawgoddard.com/en/insights/insights-briefings/2021/](http://www.addleshawgoddard.com/en/insights/insights-briefings/2021/)
energy/an-investors-guide-to-hydropower-in-africa/
70 openknowledge.worldbank.org/handle/10986/33313
71 [www.hydrosustainability.org/published-assessments/semla-iv](http://www.hydrosustainability.org/published-assessments/semla-iv)

71 [www.hydrosustainability.org/published-assessments/semla-iv](http://www.hydrosustainability.org/published-assessments/semla-iv)
72 For additional details see: [https://www.hydropower.org/news/ihalaunches-1m-assessment-fund-for-sustainable-hydropower-projects](https://www.hydropower.org/news/ihalaunches-1m-assessment-fund-for-sustainable-hydropower-projects)
73 Note that for several projects, two or even three data points were
available as the information was sufficiently granular. For example,
a project could have cost information on electrical installations and
civil works.

47 [www.hydroreview.com/hydro-industry-news/voith-hydrocompletes-modernization-work-on-1000-mw-drakensberg-pumpedstorage/#gref](http://www.hydroreview.com/hydro-industry-news/voith-hydrocompletes-modernization-work-on-1000-mw-drakensberg-pumpedstorage/#gref)
48 [www.nsenergybusiness.com/projects/abdelmoumen-pumped-](http://www.nsenergybusiness.com/projects/abdelmoumen-pumped-)

approved, pending regulator approval or announced.
77 Based on IHA Hydropower Database
78

D3.2-Value-of-storage.pdf
53 / [www.policycenter.ma/opinion/digitalization-future-energy-africa](http://www.policycenter.ma/opinion/digitalization-future-energy-africa)
54 [www.iea.org/reports/climate-impacts-on-african-hydropower](http://www.iea.org/reports/climate-impacts-on-african-hydropower)
55 [www.hydropower.org/publications/hydropower-sector-climate-](http://www.hydropower.org/publications/hydropower-sector-climate-)

Based on IHA Hydropower Database
78 Some stations were included based on discussions of potential
need with AfDB.
79 The form was also translated into French for companies operating

resilience-guide
56 [www.climatepolicyinitiative.org/wp-content/uploads/2022/09/](http://www.climatepolicyinitiative.org/wp-content/uploads/2022/09/)
Landscape-of-Climate-Finance-in-Africa.pdf
57 [www.hydropower.org/sediment-management-case-studies/sudan-](http://www.hydropower.org/sediment-management-case-studies/sudan-)

need with AfDB.
79 The form was also translated into French for companies operating
in francophone countries
80 [www.sciencedirect.com/science/article/pii/](http://www.sciencedirect.com/science/article/pii/)
S0960148121000471?dgcid=rss\_sd\_all
81 See section 3

57 [www.hydropower.org/sediment-management-case-studies/sudanroseires](http://www.hydropower.org/sediment-management-case-studies/sudanroseires)
58 [www.researchgate.net/publication/263007058\_Modelling\_of](http://www.researchgate.net/publication/263007058_Modelling_of)\_

58 [www.researchgate.net/publication/263007058\_Modelling\_of](http://www.researchgate.net/publication/263007058_Modelling_of)\_
sedimentation\_processes\_inside\_Roseires\_Reservoir\_Sudan
59 [www.hydropower.org/sediment-management-case-studies/](http://www.hydropower.org/sediment-management-case-studies/)

59 [www.hydropower.org/sediment-management-case-studies/](http://www.hydropower.org/sediment-management-case-studies/)
malawi-kapichira
60

81 See section 3
82 The total power of the African hydropower fleet is taken
from the IHA Status report 2022: [https://www.hydropower.org/](https://www.hydropower.org/)
publications/2022-hydropower-status-report. In 2022 IHA updated
this figure to 40 GW.
83 This figure is based on a study focused on the European fleet,

60 The capacity factor is the ratio of actual electrical energy output
over a given period of time to the theoretical maximum electrical
energy output over that period
61

83 This figure is based on a study focused on the European fleet,
indicating achievable power increase between 5% and 11.6% when
replacing old, deteriorated turbines based on outdated technology.
“Assessing the energy potential of modernizing the European
hydropower fleet”, Emanuele Quaranta and others, 2021. [https://doi](https://doi/).
org/10.1016/j.enconman.2021.114655

the two parties agree to buy and sell an amount of energy which
is to be generated by a renewable asset at a price determined by a
specific contractual clause. This is generally long-term agreement
covering a period between 10-20 years.
67

84 This figure are based on a study focused on the European fleet
and indicated achievable power increase up to 11.6%.
“Assessing the energy potential of modernizing the European
hydropower fleet”, Emanuele Quaranta and others, 2021. [https://doi](https://doi/).

D00XbP0Q-
63 [www.hydropower.org/sites/default/files/publications-docs/](http://www.hydropower.org/sites/default/files/publications-docs/)
Better%20Hydro%20Compendium%20of%20Case%20Studies%20
2017.pdf

2017.pdf
64 tractebel-engie.com/en/references/nalubaale-and-kiirahydropower-plants
65 [www.afdb.org/sites/default/files/documents/environmental-and-](http://www.afdb.org/sites/default/files/documents/environmental-and-)

67 Dupraz, C., 2019. ‘Modernisation Strategies’ Swiss Federal Office
off Energy presentation, World Hydropower Congress 2019.

87 A detailed assessment on the implication of the Awash River
Bassin is available at this link: [https://www.hilarispublisher.com/openaccess/awash-rivers-the-ongoing-irrigation-practices-future-projectsand-its-impacts-on-the-environment-of-awash-river-basin-73509.html](https://www.hilarispublisher.com/openaccess/awash-rivers-the-ongoing-irrigation-practices-future-projectsand-its-impacts-on-the-environment-of-awash-river-basin-73509.html)
88 whc.unesco.org/en/list/509/
89 [www.hydropower.org/sustainability-standard](http://www.hydropower.org/sustainability-standard)

* * *

Africa Hydropower Modernisation Programme Continent-wide mapping of hydropower rehabilitation candidates

**Disclaimer** The views expressed in this publication are those of the authors and do not necessarily reflect the views and policies of the African Development Bank (AfDB), its Board of Governors, its Board of Directors or the governments they represent.

AfDB and its Board of Directors do not guarantee the accuracy of the data included in this publication and accept no responsibility for any consequence of their use. The study was intended to be a high-level screening exercise to identify potential candidate hydropower stations for modernisation at a continental scale in Africa. The information provided in this study is not a comprehensive, detailed analysis and is not intended to be used to decide on specific plant-level modernisation design requirements.

By making a designation or reference to a particular geographical area or using the term “country”, AfDB does not intend to make any judgments as to the legal or another status of any territory or area.

AfDB encourages printing and copying information exclusively for personal and non-commercial purposes with proper acknowledgement of AfDB. Users are restricted from selling, redistributing, or creating derivative works for commercial purposes without the express written consent of AfDB.

Utilising this document is intended and authorised only for the benefits of the personnel employed by the African Development Bank.

* * *

**Sustainable Energy Fund for Africa (SEFA)** African Development Bank Group Immeuble du Centre de commerce International d’Abidjan CCIA

Avenue Jean-Paul II 01 BP 1387 Abidjan 01, Côte d’Ivoire

[www.afdb.org/sefa](http://www.afdb.org/sefa)

**© 2023 African Development Bank** **All rights reserved**