Clean energy can help to ease the water crisis

Energy is thirsty

The world has a water problem – and the energy sector needs to contend with it. About a quarter of the global population does not have access to safe drinking water and almost half lack proper sanitation services. Nearly two-thirds of the world’s population experiences severe water scarcity for at least one month each year, and climate change will make water flows more erratic.

At the same time, the global energy system used around 370 billion cubic metres (bcm) of freshwater in 2021, or roughly 10% of total global freshwater withdrawals. Water is essential for almost every aspect of energy supply, from electricity generation to fossil fuel production to biofuels cultivation.

World Water Day is an annual event aimed at bringing attention to sustainable water management and this year’s theme is “accelerating change”. This commentary explores how an acceleration in clean energy development can help ease the world’s water crisis. The choices we make for future energy pathways will have a major impact on our ability to achieve Sustainable Development Goals, including access to clean water and Sanitation for all.

Energy uses less water in a net zero emissions pathway

In the Net Zero Emissions by 2050Scenano(NZE) – our most ambitious scenario – water withdrawals by the energy sector decline by almost 20 bcm by 2030. The biggest reductions happen in the power sector, where withdrawals fall nearly 15% as coal-fired power generation is quickly replaced by solar PV and wind. Greater energy efficiency also plays an important role in reducing the volume of water needed to meet global energy demand.

Water stewardship is critical for energy security

The power sector is particularly vulnerable to growing water stress, and increasing water shortages in dry regions are a major source of concern for energy security. Hydropower generation could decline significantly in regions where water flows are likely to decrease, such as southern Europe, North Africa and the Middle East. Fluctuations in hydropower output have already exacerbated the global energy crisis: lower hydropower availability in Latin America in 2021 led to increased demand for liquified natural gas, contributing to early pressure on natural gas prices. In 2022, a very poor year for hydropower in southern Europe added to the strains on gas and electricity markets caused by Russia’s invasion of Ukraine and the related cuts to pipeline gas deliveries.

Thermal power plants often require water for cooling. France’s Chooz nuclear power plant was closed for around two months when a severe drought hit in 2020, and several other plants had to reduce output in 2022 due to lack of cooling water.

Water stress also poses risks to the transport of fuels and materials. In 2022, droughts and severe heatwaves led to low water levels in key European rivers such as the Rhine, limiting barge transport of coal, chemicals and other materials.

Water availability is an increasingly important measure for assessing the physical, economic and environmental viability of energy projects. Some energy producers are turning to alternative water sources and water recycling to help reduce freshwater constraints. There is also significant scope to lower water use by improving the efficiency of the power plant fleet and deploying more advanced cooling systems for thermal generation.

An integrated approach to energy and water management can help reduce risks on both fronts. Many of the clean technologies being deployed to provide electricity can also be used to provide access to water. Decentralised solar PV water pumps can replace more expensive diesel pumps and mini-grids can power filtration technologies, such as reverse osmosis systems, to produce clean drinking water. Also, water services can provide an “anchor load” for power generation and assist with balancing and storage. For example, irrigation can be shifted to periods of low electricity demand, while pumping to storage facilities can be reduced during demand peaks. Energy and water stewardship should go hand in hand.