The energy industry currently accounts for around 15% of the world’s total water use, the International Energy Agency (IEA) said.
It revealed global water withdrawals for energy production in 2010 were estimated at 583 billion cubic metres (bcm), out of which water usage – that was withdrawn but not returned to its source – was 66bcm or around 11%.
Water is critical for electricity generation as well as the extraction, transport and processing of fossil fuels and the irrigation of crops that go into biofuels. Water shortages in India and the US, among other countries, have however limited energy output in the last two years while the “heavy use of water in unconventional oil and gas production has generated considerable public concern”, the IEA said.
Its report looked at three difference scenarios – the New Policies Scenario, the Current Policies Scenario and the 450 Scenario.
Global water withdrawals for energy production reach 690bcm in 2035 in the New Policies Scenario, with growth slowing after 2020. Withdrawals in the Current Policies Scenario – which assumes no change in existing energy-related policies – continue to rise throughout the projection period, climbing to 790bcm in 2035.
The IEA’s 450 Scenario “sets out an energy pathway consistent with the goal of limiting the global increase in temperature to 2°C by limiting concentration of greenhouse gases in the atmosphere to around 450 parts per million of CO2″.
Under this scenario, it could be less water-intensive – with withdrawals expected to reach only 600bcm in 2035 – with much more modest energy demand compared to the New Policies Scenario and a “marked shift in the power sector” away from coal-fired power plants and towards renewables.
It widely deploys technologies including nuclear power, power plants with carbon capture and storage (CCS) and conventional biofuels “whose high water use requirements must be taken into account when citing energy production facilities”, the IEA said.
Maria van der Hoeven, IEA Executive Director said: “Water availability is a growing concern for energy and assessing the energy sector’s use of water is important in an increasingly water-constrained world.
“Since water and energy are essential resources, we need to find ways to ensure that use of one does not limit access to the other. As demand for both continues to increase, this will be a growing challenge and priority.”