The water it takes to supply energy to California, the biggest U.S. fuel market, has risen almost four-fold over two decades. And the culprit isn’t oil. It’s biofuels, according to a report. California’s “water footprint” for energy — the water used to produce transportation fuels, natural gas and electricity consumed in the state — rose to 7.7 cubic kilometers in 2012 from 2.1 in 1990, the report prepared by university and environmental researchers showed. Almost all of the increase came from water used to grow biofuel crops in the U.S. Midwest and overseas to help meet the state’s goals for using low-carbon fuels, according to the paper published by the journal Environmental Science & Technology. The increase in water demand for biofuels highlights an unintended consequence of low-carbon fuel policies being adopted and considered across the U.S. to curb global warming and reduce the nation’s dependence on […]