Solar thermal is heating up.
Infinia, which makes a Stirling engine that can generate electricity or household heat by harvesting heat from the sun, has raised $9.5 million, the company said Thursday. Investors include Idealab and Khosla Ventures. As part of the deal, Infinia bought Stirling Cycles, one of Idealab's companies.
Stirling engines were invented in the 19th century as an alternative to steam engines. A Stirling motor has a closed cylinder that houses a gas, such as hydrogen, and a piston. Applied heat expands the gas to move the piston that, in turn, pumps other mechanisms, such … Read more