A Chinese dairy farm took the excrement from 60,000 of its 250,000 cows and converted it into electricity. Talk about green! They generate about 5.66 megawatts of power and that's roughly enough power some 3500 homes.

Technology Review says that the Huishan Dairy created a methane converter that is over 10 times the size of similar devices and it is powered by four of the GE engines you see in the picture above. The converter than captures methane from fermenting cow dung and turns it into power.

This is a rather innovative way to go green, and methane converters are only used in about 1% of farms, which is unfortunate, considering the amount of electricity one can save. [Technology Review via PopSci]