To date,Google has invested over $680 million in innovative clean energy companies and projects through Google.org, Google Ventures and Google corporate investments. Google intends to supporte cleantech companies with scalable and potentially breakthrough technologies that could produce renewable energy cheaper than coal.  Some of the google's investments in clean energy - 

Today Google announced a $280 million investment to create a fund, in partnership with SolarCity, to help the company finance more solar installations across US.This is Google's first investment in "distributed" renewable energy (generated and used right at home). The investment is expected to be a  quadruple-win for Google, SolarCity, the environment, and new customers who get access to clean energy at a economic rates.