Bloom Energy has unveiled its 100KW Energy Saver fuel cell at eBay's Silicon Valley HQ, attended by many notaries, including State Governor Arnold Schwarzenegger.
The Energy Saver is a solid oxide fuel cell that converts almost any fuel source into electricity, according to the company.
Each Energy Saver unit contains thousands of fuel cells, and even when burning fossil fuel is 67 per cent cleaner than a coal-fired power plant.
The device was originally developed for the NASA Mars space programme. Each unit is about the size of a parking space and can generate enough power for about 100 homes.
Google gets in early
So far, the customers for the unit include Google, Coca-Cola, Staples, and eBay. As John Donahoe, CEO of eBay, said at the launch: "When Bloom came to us, it was an easy decision to become an early adopter of its cutting-edge new technology.
"As a result, we are meeting financial and environmental goals, while fuelling a more energy efficient global marketplace. That's good for us, our customers and the planet."
Although the Bloom Energy Saver has just been officially launched, Google has already been using one for 18 months.
It claims that it's experienced some significant savings in energy costs, and the only problem to date has been a few clogged air filters.
Rick Needham, manager of Google's green business operations, noted: "As we work hard to reduce Google's environmental footprint and improve our sustainability, we are pleased to be able to use on-site clean power generated by Bloom Energy."