The power of water, sun and wind: Advancing renewable electricity supply in West Africa

Hydropower plant in Ghana. Photo by Sebastian Sterl.

Latest publication in Nature Sustainability by ZEF guest researcher and CIREG project member Sebastian Sterl shows the potential of renewable energy in West Africa.

Not only Germany but also West Africa is on the verge of an energy turnaround. Its population is growing, urban areas are expanding, industries and electrification are advancing. The demand for reliable power supply is increasing accordingly. Until now, West Africa has been heavily dependent on natural gas, which covers more than 50% of its total electricity supply, supplemented by hydropower. An international team of modelers from the Vrije Universiteit Brussel (VUB) and the KU Leuven (KUL), both in Belgium, and the Center for Development Research (ZEF) of the University of Bonn in Germany, have now calculated how a sustainable and reliable energy transition, breaking with the “natural gas and hydro” paradigm and diversifying towards clean solar photovoltaic (PV) and wind power in West Africa, could be kick-started. They developed a new computer model and used detailed water, weather and climate data from the region for their calculations. Their results were published in: Sterl, S., Vanderkelen, I., Chawanda, C.J. et al. Smart renewable electricity portfolios in West Africa. Nat Sustain (2020). https://doi.org/10.1038/s41893-020-0539-0

The power of hydropower

According to the scientists, existing and planned hydropower may play a key role for such a green transition in West Africa. "Solar and wind energy vary on all time scales from hourly to annual, which means grid operators are often hesitant about their take-up," says Sebastian Sterl, lead author of the study. "Hydropower is an ideal lever to support the uptake of solar and wind power, because it can be used highly flexibly and generates considerably lower CO₂ emissions than natural gas".

West African Power Pool

For West Africa to successfully integrate high shares of solar PV and wind power in its electricity mix, however, greater regional cooperation and networking in energy production would be paramount, the study says. The scientists propose that a "West African Power Pool", which would connect national power grids on an intra-regional basis, may provide an ideal way to increase the potential for integrating variable renewable resources on the grid. This is because the spatial distribution of hydro, solar and wind power potential is highly uneven.

Countries with a tropical climate, such as Ghana and the Ivory Coast, typically have a huge potential for hydropower and quite high levels of solar radiation, but hardly any wind. The drier countries like Senegal and Niger have little potential for hydropower, but more sunshine and wind. All measures taken together would make it possible that about 60% of the current electricity demand in West Africa could be covered by complementary renewable electricity sources: Half from solar and wind power, the other half from hydro-electric power, without the need to build or use large batteries or other storage facilities. According to the study, within a few years the cost of solar and wind power generation in West Africa should also fall to such an extent that the proposed solar-wind-water strategies will provide cheaper electricity than gas-fired power plants.

Better ecological footprint

However, hydroelectric power plants can also have negative impacts on local ecosystems. In many developing countries, piles of controversial plans for new hydropower plants have been developed. The study can help to make future investments in hydropower more sustainable. "By making the best possible use of existing and planned hydroelectric power plants to massively promote solar and wind energy, we can even simultaneously do without building some new dams," says Sterl. "In this way, the CO₂ emissions from gas-fired power plants as well as the environmental damage caused by the overuse of hydropower can be reduced ".

Global significance

The methods developed for the study are easily transferable to other regions, and the research has global relevance. Sterl: "Almost all regions with a lot of hydropower or hydroelectric potential could use these results to compensate for deficits in solar and wind energy, and thus increase the share of renewables in their power mix". Various European countries, with Norway in the lead, have shown increased interest in recent years in using their hydropower to support solar and wind energy in EU countries. By exporting Norwegian hydropower at a time when other countries are experiencing shortages of solar and wind energy, European energy change could also be promoted.

Publication: Sterl, S., Vanderkelen, I., Chawanda, C.J. et al. Smart renewable electricity portfolios in West Africa. Nat Sustain (2020). https://doi.org/10.1038/s41893-020-0539-0

This study was carried out within the framework of the CIREG project (cireg.pik-potsdam.de) with support from the European Union and the Belgian Office for Science Policy (BELSPO).

German press release /Lesen Sie den deutschen Pressetext hier.

Contact Sebastian STERL (Vrije Universiteit Brussel, Katholieke Universiteit Leuven, guest researcher at ZEF)

E-mail: sebastian.sterl@vub.be / sebastian.sterl@kuleuven.be

Phone: +31 617 37 57 96