A new report from the United Nations warns that rising demand for energy, from bio-fuels to shale gas, is a threat to freshwater supplies that are already under strain from climate change.
It urged energy companies to do more to limit use of water in everything from cooling coal-fired power plants to irrigation for crops grown to produce bio-fuels.
“Demand for energy and freshwater will increase significantly in the coming decades,” UN agencies said in the World Water Development Report according to Reuters Newsagency.
“This increase will present big challenges and strain resources in nearly all regions.”
By 2030, the world will need 40 per cent more water and 50 per cent more energy than now, the report said.
Reuters reports water is under pressure from factors such as a rising population, pollution and droughts, floods and heatwaves linked to global warming.
Around the world, about 770 million of the world’s seven billion people now lack access to safe drinking water, it said.
At the same time the energy sector accounted for about 15 per cent of water withdrawals from sources such as rivers, lakes and aquifers.
“This interdependence calls for vastly improved cooperation” between water and energy, said Irina Bokova, Director-General of UNESCO.
The report lamented the lack of influence of the water sector compared to what it called the “great political clout” of energy.
March 22 was World Water Day in the UN calendar.
All energy production used water, often as a coolant, it said.
Least water was used in wind and solar power, while heavy users included hydraulic fracking to produce shale gas or the extraction of oil from tar sands.
Hydropower dams were sometimes built with little thought for other water users, and the report urged caution about bio-fuels, partly because of water used for irrigation.
“China and India, the world’s two largest producers and consumers of many agricultural commodities, already face severe water limitations in agricultural production, yet both have initiated programs to boost bio-fuel production,” it said.
Zafar Adeel, head of the UN University’s Institute for Water, Environment and Health, said that governments should re-think subsidies for both energy and water.
“Pricing water is much more challenging” than energy, he told a telephone news briefing.
The UN General Assembly declared water a human right in 2010, strengthening arguments that basic supplies should be free.
Energy companies say they try to limit water use.
Reuters reports Exxon Mobil, for instance, said that net freshwater consumption at its operations fell 11 per cent to 2.1 billion barrels in 2012 from 2011.
The UN study said there were examples where energy could successfully recycle water.
In Stockholm, buses and taxis run on biogas produced from waste water, which is rich in methane.
