In Sub-Saharan Africa, there are huge opportunities for countries to trade renewable energy, enabled by interconnected power systems. While importing energy from another country or region might be seen as a risk (as being experienced in Europe, where countries are trying to reduce their dependence on Russia's oil and gas following Russia’s invasion of Ukraine) – trading electricity generated from renewable energy resources across borders can actually help to meet energy demands, bolster security of supply, and assist the transition to clean energy. Simon Trace, programme director of the Energy and Economic Growth (EEG) research programme, funded by the UK’s Foreign, Commonwealth & Development Office (FCDO), explains more.
Harnessing Sub-Saharan Africa’s diverse and abundant renewable resources, which include sunshine, wind, river systems and geothermal energy, has the potential to improve energy access and meet growing energy demands, while also addressing climate change. Furthermore, in recent years, the cost of renewable power has been declining*, making it increasingly viable.
However, integrating electricity generated from renewable sources into conventional power grids at scale presents significant technological challenges. Weather-dependent renewable sources, especially wind and solar, are inherently intermittent and uncontrollable; the sun will generate electricity only in daylight hours, and the wind doesn’t always blow. The amount of solar or wind energy available can also change across short time periods (hours to days). This variability can lead to grid stability issues, which can affect reliability of supply.
Linking areas with high energy demand to places with high renewable energy generation potential (which may be quite far apart) can help to balance supply and demand, overcome intermittence issues and improve energy security.
For example, the sun might not be shining in country X, but, at the same time, it might be shining in country Y, where there might be surplus energy to export – especially if the countries are in different time zones and their peak energy demand patterns differ. When the sun rises on the east coast of Africa, people in West Africa (where it is night-time) could be charging their electric vehicles or cooking using solar power from the east. Countries that regularly experience power outages (such as South Africa) could tap into surplus resources to meet their energy demands and improve energy security.
Cross-border renewable energy trading is made possible through large-scale regional and international ‘green grid’ electricity interconnections. Through advances in transmission technology, power can be transmitted over very long distances with very little loss. For example, China recently completed a 970-mile-long ultra-high-voltage direct current line to bring solar and wind power from Tibet to China’s centre. It followed construction of a cable that can supply Shanghai with power from the deserts and mountains of Xinjiang province, around 2,000 miles away.
The development and deployment of green grids is gaining momentum and engagement from leaders across the world. Indeed, during COP26, the Prime Ministers of the UK and India announced the Green Grids Initiative – One Sun One World One Grid, which has been endorsed by over 90 countries.
In Africa, electricity is already traded between countries across ‘power pools’ (electricity systems and markets shared across economic blocs) and potentially between pools, to help meet domestic demand or sell excess supply. There are five independent regional power pools covering the whole continent, each managing its own interconnectivity with different levels of integration. There is an aim to link them together; connecting all 55 countries on a single grid, it would be the biggest interconnection in the world in geographical terms.
African countries have already committed to several concrete interconnection projects. For example, the Africa Working Group of the Green Grids Initiative is exploring possibilities to accelerate the realisation of the ZiZaBoNa Transmission Line to link up Zimbabwe, Zambia, Botswana and Namibia, and a link between the Inga 3 hydropower project (construction of a third dam on the Inga Falls of the Congo River) in the Democratic Republic of the Congo and Southern Africa.
There are, however, many challenges surrounding cross-border energy trading. Outside the need for significant financial investment, the most obvious one is political. There can be mistrust between neighbouring countries, and countries within a region may not have good relationships – and even if they do, things may change in the future. But equally, it is thought that regional power trade can help to strengthen mutual confidence and cooperation among countries.
Internally, some developing countries may also have concerns over the political advisability of selling electricity to other countries while their domestic populations still lack access to energy, even if that meant access could be extended to all in the long term.
Furthermore, installing wind and solar in areas with the fastest wind speeds or the highest solar radiation is not always the most cost-effective strategy from an overall system perspective, nor is it necessarily the most environmentally or socially beneficial. As being explored in this EEG project, optimal energy development pathways should ideally be shaped by goals to protect biodiversity and areas important to local communities.
While there are many challenges to cross-border renewable energy trading – not least the need to mobilise funds to build green grid infrastructure – linking renewable resources together could create a reliable supply of affordable, clean, secure energy across large areas of Sub-Saharan Africa that could potentially meet demand in any place, at any point in time.
*Excluding hydropower, an already advanced technology.
By Simon Trace,
Director of the Energy and Economic Growth (EEG) research programme
