Energy is vital to a well-functioning water sector

Today is World Water Day, an annual event aimed at bringing attention to the importance of sustainable water management. This year’s theme is “water for peace,” highlighting the critical role access to water plays in political stability and human prosperity. Currently, 2 billion people do not have safe drinking water, and around two-thirds of the world’s population experiences water shortages for at least one month each year. Water shortages are likely to grow in many regions due to climate change and increasing water demand, driven by population growth and economic development.

Water and energy are two closely interdependent critical resources. Water is essential for almost every aspect of producing energy, from electricity generation to fossil fuel extraction to biofuels cultivation. The energy sector accounts for roughly 10% of total global freshwater use. Meanwhile, maintaining global water supply is dependent on energy. Energy is needed to extract water from lakes, rivers and oceans; lift groundwater from aquifers and pump it through pipes and canals; and treat water and deliver it to users.

This commentary explores how energy is being used to ensure reliable water supply and even help ease the world’s water crisis – with a focus on the Middle East, where the level of water stress is extremely high. It also explains the connections between water, energy and climate, and highlights technologies and policies that can create beneficial synergies between them. 

Almost all of the world’s water demand is met by groundwater and surface water. However, water stress has led to an increase in the use of non-traditional resources, such as saltwater. This requires desalination, the process of separating saline water (seawater or brackish water) into freshwater and concentrated salt. Global energy demand for desalination has nearly doubled since 2010, and current trends point to another doubling to 2030. Some 21 000 desalination plants currently operate in about 150 countries, from the United States and China to Sub-Saharan Africa and Southeast Asia – though half of global installed capacity is located in the Middle East and North Africa. 

The Middle East has one of the lowest levels of freshwater use per capita in the world. With a growing population and easy access to seawater, desalination is the main approach used to tackle water scarcity. Desalinated water covers the majority of daily water needs in many countries in the region, including Qatar, Kuwait, Bahrain, Oman and Saudi Arabia, and new projects to expand desalination capacity are underway. Jordan is planning a major plant on the Gulf of Aqaba that will increase its desalination capacity from 4 billion to 350 billion litres each year – enough to supply a city of 2.5 million people. Saudi Arabia plans to construct a new city with 9 million people in the northwest part of the country by 2045 that will depend on desalinated water from the Red Sea and the Gulf of Aqaba.

Desalination is energy-intensive, often requiring over 1 kilowatt-hour per cubic metre of water treated. In 2023, the energy used by desalination services in the Middle East was equivalent to almost half of all energy consumed by the region’s residential sector.

More than 95% of this energy came from fossil fuels. In the Middle East, the low cost of oil and gas, and the prevalence of co-generation facilities for power and water, means countries rely heavily on fossil fuel-based thermal desalination instead of membrane desalination, which is more common elsewhere. The region accounts for roughly 90% of the thermal energy used for desalination worldwide.

In IEA projections based on current policy settings, growing demand for desalination pushes its share of final energy consumption in the Middle East to 10% in 2030 and 15% in 2050, up from 7% today. In 2030, the energy needed for desalination in the region is set to be equivalent to around 80 billion cubic metres of natural gas, more than Egypt’s production in 2022.

Climate change will continue to exacerbate water stress. Changing precipitation patterns with more frequent droughts and floods are challenging water management, while sea-level rise, combined with groundwater extraction, is leading to saltwater intrusion in various locations, reducing the availability of freshwater. Increasing temperatures and aridity in some places could add to pressures, causing spikes in water demand while surface water is evaporating at faster rates. Energy infrastructure that was built for a cooler, calmer climate may no longer be reliable or resilient enough as temperatures climb and weather events become more extreme.

Growing strain from climate change is projected to result in higher energy consumption for water supply. More desalination plants are expected to be commissioned, and governments have started pursuing major transportation projects to move water to where it is scarce. If desalination grows in a highly energy- and emission-intensive way, this could lead to a vicious cycle – producing more emissions and, in turn, more extreme weather. 

Cleaner technologies can help stop this. Membrane-based desalination, which removes salt by pushing water through a series of membranes, is less energy intensive than thermal desalination and can be powered by renewables. And solar-powered desalination has been a topic of interest since the early 1980s, when the first commercial pilot plant was commissioned in the Middle East. In 2018, the world’s first large-scale desalination plant powered by solar PV was completed in Saudi Arabia. It has a production capacity of 22 billion litres per year, sufficient to supply a city of about 150 000 people. The region is also looking to make more efficient use of water resources and re-use wastewater, having doubled the number of water reuse projects every decade since 1990.

Energy and water are resources that are closely linked. Both are foundational to economic development, food production, environmental sustainability and human well-being. Ensuring reliable, affordable, and sustainable access to energy and water is critical for the advancement, prosperity and stability of societies.

Policies, partnerships and cooperation are key to achieving these aims. Governments can replace unnecessary energy and water subsidies with more targeted support, encouraging more efficient use of these resources and lowering associated emissions. Partnerships and cooperation, meanwhile, can facilitate access to water and energy where it is most needed and promote conservation by reducing losses and inefficient practices.

An integrated approach to energy and water management can help reduce risks across the board. Many of the clean technologies that are being deployed to provide electricity worldwide can also be used to provide access to water. For example, water pumps powered by decentralised solar PV can replace more expensive diesel pumps, and mini-grids can power filtration technologies, such as reverse osmosis systems, to produce clean drinking water. A shift from fossil fuels to renewables in the power sector can lower energy’s water requirements. Extractive industries can help by reducing their water needs and using better treatment technologies.

Measures to save water and use it more efficiently also ease demand for energy. Smart water re-use and recycling can lower treatment requirements and reduce related energy needs. Energy and water stewardship should go hand in hand.