How West Africa can expand power supply and meet climate goals
Not too
long ago, when the idea of solar and wind energy was still hotly debated,
critics used to point out the limitations of these energy sources: the sun
doesn’t always shine and the wind doesn’t always blow. But nowadays many
countries’ electricity grids are strongly supplied by renewable
energy.
The
challenge in creating flexible, reliable and affordable energy supply systems
with renewables lies in the very different circumstances across countries and
regions. Planning and expanding renewable power must consider countries’ local
resources and their existing and planned infrastructure. This becomes even more
interesting for countries trying to grow their grids and expand their
renewables at the same time – like many in sub-Saharan Africa.
One
technology that has the flexibility to complement solar and wind power
production is hydropower. It can be used as a constant source of electricity,
but also compensate for fluctuations in other sources. But it does need to be
properly planned and managed if it’s to be sustainable.
Since
power generation infrastructure lasts for 30 to 50 years, decisions taken today
will to a large extent determine whether governments can meet their climate targets.
Across
West Africa, many countries grapple with the challenge of rising electricity
demand. At the same time, climate change impacts, mostly caused by fossil fuel
combustion, are having a heavy impact on the region’s weather
patterns and potentially agricultural yields.
Can
increased electricity generation be harmonised with climate change objectives?
Our research shows
that combining sustainably managed hydropower plants with new solar and wind
power projects is a promising option for the West African region. It could
minimise the use of fossil fuels and their negative climate change impacts as
the region seeks to expand access to affordable electricity.
West African Power Pool
Countries
in West Africa have different renewable energy potentials. Solar
potential exists nearly everywhere. Wind
potential is strongest along coastal areas and in the northern, drier
part of the region. Hydropower potential is mostly concentrated in the southern
part of the region, which receives the most
rainfall.
Many
countries already use large hydropower plants, such as Ghana’s Akosombo dam,
and many new dams are in the planning. Solar and wind power
are more recent additions.
Cross-border
electricity trade could make better use of all this hydropower, coupled with
solar and wind. A common power pool, allowing countries to share their
resources, could increase reliable, renewable power supply by as much as 60%,
according to our research.
The
diagram below, based on our paper, illustrates an example of countries’
potential contributions to such a power pool.
West
African countries do already collaborate on electricity exchanges, but mostly
through bilateral contracts. The West
African Power Pool, a regional agency, is planning to integrate the
national power systems into a unified electricity market on a larger scale. Our
research shows how these efforts could be streamlined with the growth of
renewable electricity sources.
Similar
efforts are under way in other parts of the world, such as the European Union,
where cross-border
cooperation is also expected to become more important to scale up
renewable electricity generation.
Benefits for health, costs and ecology
In our
paper, we use a new model to
examine the synergies of sustainable hydropower generation with solar and wind
power in West Africa. The model shows how to manage these sources in
combination.
We show
that the region can use hydropower, rather than natural gas plants, to ensure
grid reliability while increasing solar and wind power. Natural gas is often
touted as a bridging fuel in the transition to sustainable energy. But global
emissions need to be around zero by mid-century according to the Paris Agreement. Building more gas
infrastructure therefore risks missing climate goals.
The
negative impacts on health from air
pollution resulting from burning fossil fuels are also well known.
This can be avoided by investing in renewable energy.
We argue
that the cost of renewable electricity over a plant’s lifetime is likely to
soon become significantly
cheaper than for fossil fuels. This is primarily thanks to decreases
in solar photovoltaic costs.
The way forward
Our paper
shows one way to start the renewable transition for West Africa is by
optimising the use of local solar, wind and water resources while keeping an
eye on sustainability criteria. For instance, our methodology ensures that
hydropower lake levels and downstream river flows remain within acceptable
boundaries. It also underlines the possibility of replacing future hydropower
plants with solar and wind.
This will
increase the overall ecological sustainability of renewable power generation.
Taken
together, such measures will help to pave the way for a long-term
transition towards solar PV-based power systems, supported by wind,
hydropower, and battery storage.
Our study
framework is not limited to West Africa. It can be used for other regions that
depend heavily on hydropower and also seek to increase solar and wind power
generation.
West
African countries are not yet locked in to large, integrated power grid
infrastructure designed for plants powered by fossil fuels, as is the case in
Europe and North America. The region can plan its future grids around
renewables from the outset. It’s an opportunity to leapfrog old technologies –
one which other parts of the world have never had.
AGM
Source
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