IT’S WATER OR ENERGY UNLESS IT’S WIND OR PV

Water shortages threaten renewable energy production, experts warn; Thinktank says technologies reliant on water could be hampered by droughts – and production is faltering already
Suzanne Goldenberg, 27 June 2011 (UK Guardian)

"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 [The Water-Energy Nexus; Adding water to the energy agenda from World Policy Institute]…

"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…"

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"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…Solar thermal farms use five times as much water as nuclear power plants…In contrast, photovoltaic solar cells, which convert energy from the sun into electricity, [and wind turbines, which convert the mechanical energy of wind into electricity,] use minimal amounts of water."

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"Meanwhile, the US drought is forcing energy companies to scale back plans for deploying new techniques in hydraulic fracturing ("fracking") for oil and gas extraction. Not long ago, energy companies were hoping to increase production in Texas by 50% over the next five years…Unlike in Pennsylvania, where the chemicals used in natural gas drilling have contaminated drinking supplies, the problems in Texas are a matter of water quantity, not water quality…

"It takes up to 13m gallons of water to open up a single well in the Eagle Ford shale region in south Texas, where water is in perennially short supply. Such demands are going to block development of areas in south and west Texas, which are suffering water shortages…"