Further shoring up its green credentials, Google has invested $75 million in Clean Power Ventures, a startup that makes solar power generators for homes.

The initial outlay, announced on Google's Green Blog, brings Google's total investment in renewable energy to $850 million.

Clean Power Ventures has been licensing its proprietary software to solar panel installers but will now offer a new service: connecting solar power installers with investors like Google looking to buy solar power systems.

Google's deal with Clean Power Ventures works like this: Homeowners can get solar panels installed on their roofs but won't own them. Instead, they'll sign a contract to buy the electricity generated by the panels. Google can then buy the solar panel systems from Clean Power Ventures, which gets a cut of the homeowners' monthly payments.

The announcement comes after Google invested $280 million in SolarCity — a company that helps homeowners and businesses start using solar energy as a power source.

Image courtesy of Flickr, Abi Skipp