Commentary: Energy has a Role to Play in Achieving Universal Access to Clean Water and Sanitation

The world has a water problem. More than 2.1 billion people drink contaminated water.  More than half the global population – about 4.5 billion people – lack access to proper sanitation services. More than a third of the global population is affected by water scarcity, and 80% of wastewater is discharged untreated, adding to already problematic levels of water pollution.

These statistics make for uncomfortable reading but energy can be part of the solution.

The linkages between water and energy are increasingly recognised across businesses, governments and the public – and have been a major area of analysis in the World Energy Outlook. Thinking about water and energy in an integrated way is essential if the world is to reach the United Nations’ Sustainable Development Goals (SDGs) on water: to ensure the availability and sustainable management of water and sanitation for all.

The connection works in both directions. The energy sector accounts for roughly 10% of total water withdrawals and 3% of total water consumption worldwide. Water is essential to almost all aspects of energy supply, from electricity generation to oil supply and biofuels cultivation. Energy is also required for water treatment and to move water to where it is needed; in a first-of-a-kind global assessment, the World Energy Outlook found that, on aggregate, the energy consumption in the water sector globally is roughly equal to that of Australia today, mostly in the form of electricity but also diesel used for irrigation pumps and gas in desalination plants.

With both water and energy needs set to increase, the inter-dependencies between energy and water will intensify. Our analysis finds that the amount of water consumed in the energy sector (i.e. withdrawn but not returned to a source) could rise by almost 60% to 2040. The amount of energy used in the water sector is projected to more than double over the same period.  

This challenge will be especially acute in developing countries. This is where energy demand is rising fastest, with developing countries in Asia accounting for two-thirds of the growth in projected consumption. This is also where water demand is likely to grow rapidly for agriculture as well as supply to industry, power generation and households, including those getting access to reliable clean water and sanitation for the first time. This growth will lead to higher levels of wastewater that must be collected and treated, and will require that water supply is available when and where it is needed. As such, how the water-energy nexus is managed is critical, as it has significant implications for economic and social development and the achievement of the UN SDGs, especially SDG 6 on water.

Technology is opening up new ways to manage the potential strains on both the energy and water sides, with creative solutions that leapfrog those used in the past. For example, building new wastewater capacity that capitalizes on energy efficiency and energy recovery opportunities being pioneered by utilities in the European Union and the United States could help temper the associated rise in energy demand from providing sanitation for all and reducing the amount of untreated wastewater (SDG Target 6.2 and 6.3). In some cases, achieving these targets could even produce energy:  WEO analysis found that utilizing the energy embedded in wastewater alone can meet more than half of the electricity required at a wastewater treatment plant.