African electricity generation at risk from current and future climate

Countries in southern and eastern Africa could suffer more electricity blackouts in the future because they are planning to increase the supply from hydropower dams that are vulnerable to periods of drought, warns a new report today (30 August 2018) by the Grantham Research Institute on Climate Change and the Environment and the ESRC Centre for Climate Change Economics and Policy at the London School of Economics and Political Science.

The report by Declan Conway, Patrick Curran and Kate Gannon points out that countries in southern and eastern Africa are due to more than double their hydropower capacity from 27 gigawatts today to 58 gigawatts by 2030.

However, many of the dams will be located within the same river basins and could be exposed at the same time to periods of drought.

Professor Conway, who will be presenting the findings today (30 August 2018) at the Royal Geographical Society in London, said: “The El Niño in 2015 and 2016 brought drought conditions to southern Africa and lowered water levels in dams so much that many areas experienced blackouts. If these countries build even more hydropower dams in the same river basins, they will all be at risk during future droughts, threatening further blackouts.”

The authors estimate that 82 per cent of the new hydropower capacity planned for eastern Africa would be located within the Nile basin, while 89 per cent of the new capacity for southern Africa would be in the Zambezi basin.

Professor Conway said: “Within each river basin, the new hydropower plants would be vulnerable to the same climatic variations as they would be exposed to the same patterns of rainfall. This could reduce power generation at many plants at the same time, with potentially large impacts on domestic and electricity systems.”

Many countries in southern and eastern Africa are connected through the Southern African Power Pool or the East African Power Pool.

Professor Conway said: “Unpredictable changes in water availability clearly pose significant risks to the viability of hydropower plants, as well as the electricity security of the countries. A single widespread drought could disrupt many countries at the same time, including those countries, such as South Africa, that are connected to the regional power pool but do not have many hydropower dams of their own.”

The authors also draw attention to projections from models that suggest the variability and frequency of drought events could increase in future due to climate change.

Professor Conway said: “Climate change could make the threat to hydropower plants even worse, and the impacts can be exacerbated if they affect power systems that are suffering from under-investment and poor management.”

The authors call on governments to commission independent detailed studies of the risks of concentrating hydropower plants in the same river basins, including the likely impacts of climate change.

Overseas aid organisations, such as the World Bank, should also ensure that climate-related disruptions, particularly in terms of rainfall variability and water flows, are taken into account when making decisions about support for new hydropower dams.

Professor Conway will be presenting the results at the annual International Conference of the Royal Geographical Society and the Institute of British Geographers.

For more information about this media release, or a copy of ‘Climate risks to hydropower supply in eastern and southern Africa’, please contact Bob Ward on +44 (0) 7811 320346 or r.e.ward@lse.ac.uk