趣听精彩世界：清洁能源来之不易

　　彭博商业周刊：如果全世界都能够使用页岩气，我们的清洁天然气供应量能够增加百分之四十七，既降低温室气体排放，也可降低能源价格。

　　清洁能源来之不易

　　If all the world's theoretically recoverable shale gas could be developed, our supply of clean-burning natural gas would expand 47 percent—lowering both greenhouse gas emissions and energy prices.

　　Bloomberg Businessweek says the hitch is that the process for extracting shale gas, called hydraulic fracking, sucks up as much as 25 million liters of water for each well.

　　A report from the Washington-based World Resources Institute shows that roughly 38 percent of the world's shale gas and oil lies buried beneath water-stressed regions. This means that extraction efforts will be difficult and expensive, as well as economically and environmentally risky.

　　The situation is especially true in China.