eSolar flicks switch on first US solar tower

The US solar industry ticked off a major milestone last week with the unveiling of the country's first solar thermal tower in southern California.

The 5MW Sierra SunTower solar plant features 24,000 mirrors that have been positioned to concentrate the sun's rays on two 160-foot towers containing water that is then turned into steam to drive turbines. The resulting energy is expected to provide power for more than 4,000 homes in California's Antelope Valley.

The plant has been developed by eSolar, the high-profile concentrated solar specialist which won headlines last year when it secured $130m (£77.6m) in funding from a raft of investors including Google and the Quercus Trust.

The company said that unlike other solar thermal technologies, the plant made use of advanced software algorithms to enhance efficiency and focus thousands of mirrors on a single point throughout the day.

"Today, we unveil a new blueprint for solar energy – one that leverages Moore's law rather than more steel," said Bill Gross, chief executive of eSolar, referring to the IT industry maxim that computing power increases exponentially over time.

He added that the plant would soon be followed by further projects worldwide, including the development of three plants in California and New Mexico capable of generating up to 465MW of electricity for US utility NRG Energy.

David Crane, president and chief executive of NRG Energy, hailed the opening of the new site as evidence of the commercial viability of solar thermal power, adding that the company was committed to implementing the technology on a large scale across the southwest.