Google drops $168M in California solar power tower

Google has invested $168 million into a solar power energy project led by BrightSource Energy in the Mojave desert in California, the search giant announced today.

The new project doesn’t rely on photovoltaic cells that capture sunlight and convert it electricity. Instead, if uses a large array of mirrors that focus sunlight onto a single point on a tower. The heat from the focused sunlight is used to boil water, creating steam that moves conventional turbines to generate electricity. (The idea is reminiscent of the Archimedes Death Ray, an oft-used trope in popular culture.)

The new plant will generate 392 megawatts of power — enough to take around 90,000 cars off the road over 25 years, according to Google. The average home in the U.S. uses around 920 kilowatt-hours of electricity each month.

Google also invested $5 million in a German solar power plant last week and has invested about $250 million in clean energy sources to date. The search giant has already been pushing clean technology stateside and its investment arm, Google Ventures, has invested in several clean technology companies.

BrightSource Energy’s power tower will be around 450 feet tall and use 173,000 heliostats — devices that mount two mirrors and move them to direct sunlight to the top of the tower. The project should be finished in 2013, and is also funded by NRG Energy — which also just unveiled the first of its line of electric vehicle charging stations Friday.