The solar thermal power plant business is all about big: Square miles of mirrors in the desert that surround 600-foot-tall towers to generate massive megawatts of electricity for multibillion- dollar price tags. Big Solar's ability to compete against fossil fuels, though, could come down to grains of salt.
In a small lab in the San Francisco Bay Area biotech hub of Emeryville, scientists at a startup called Halotechnics are sifting through thousands of mixtures of molten salt. They're searching for the right combinations that will allow solar thermal energy to be stored cheaply and efficiently so it can be dispatched to generate electricity after the sun sets. In other words, the 24/7 solar power plant.