from Time
http://www.time.com/time/health/article/0,8599,1713431,00.html
According to researchers at Princeton University and the Nature Conservancy,
almost all the biofuels used today cause more greenhouse gas emissions
than conventional fuels, if the full environmental cost
of producing them is factored in.
Read more:
http://www.time.com/time/health/article/0,8599,1713431,00.html#ixzz1D0OcIwwB