The development of new renewable energy technologies and other expanding sources of energy such as shale gas will be limited by the availability of water in some regions of the world, according to research by a US thinktank.
The study shows the reliance on large amounts of water to create biofuels and run solar thermal energy and hydraulic fracturing – a technique for extracting gas from unconventional geological formations underground – means droughts could hamper their deployment.
“Water consumption is going up dramatically. We are introducing all kinds of technology to reduce the carbon impact of energy, without doing anything to reduce its impact on water,” Michele Wucker, co-author of the report, told a seminar at the New America Foundation, a thinktank in Washington.
The study, estimating the water consumption of conventional and renewable energy, found even so-called clean energy solutions use vast amounts of water.
Hydroelectricity far outstrips other forms of energy in its use of water, requiring 4,500 gallons to produce a single megawatt hour of electricity – or about the amount needed to run a flat-screen TV for a year. Geothermal energy uses 1,400 gallons per MW/h.
Corn-based ethanol uses a lot of water to irrigate crops, as do nuclear plants which rely on water for cooling systems. Even some renewable energy sources – such as solar farms – are water hogs because they rely on water for cooling.