SAN FRANCISCO, CA - MARCH 22:  Samples of biodiesel sit on a pump at Dogpatch Biofuels on March 22, 2013 in San Francisco, California.  According to a report by San Francisco based nonprofit group Next 10, California continues to be the nation's leader in venture capital funding for green technology, green tech patents and the growth in clean power generation, resulting in reduced greenhouse gas emissions despite a growth in population.  (Photo Illustration by Justin Sullivan/Getty Images)