 Pernick and Wilder highlight eight major clean technology sectors : solar power , wind power , <unk> , green buildings , personal transportation , the smart grid , mobile applications , and water filtration . Six major forces , which they call the six C ’ s , are pushing clean technology into the mainstream : costs , capital , competition , China , consumers , and climate . Very large corporations such as <unk> , Toyota and Sharp , and investment firms such as Goldman Sachs are making multibillion @-@ dollar investments in clean technology . 
