ESolar

About ESolar

eSolar emerged in 2007 from the Idealab incubator, founded by lifelong entrepreneur Bill Gross, who applied his extensive background in software and technology to the renewable energy sector. Gross, a Caltech mechanical engineering graduate, had a history of successful ventures, including the sale of an educational software publisher to Vivendi. His interest in solar energy dates back to high school, and with eSolar, he aimed to make solar power competitive with fossil fuels by focusing on a design philosophy of "more software, less steel".

The company specialized in concentrated solar power (CSP) technology, specifically a power tower configuration. Its approach involved using fields of small, mass-manufactured mirrors called heliostats, controlled by advanced software to track the sun and focus its rays onto a central receiver atop a tower. This concentrated heat would boil water to create superheated steam, which then drove a turbine to generate electricity. A key differentiator was the modular and scalable design; plants were conceived in 46 MW blocks that could be aggregated to create larger facilities, offering flexibility in deployment. The firm also explored molten salt technology to store thermal energy, allowing for power generation even when the sun wasn't shining.

eSolar's business model transitioned from initially developing its own power plants to licensing its technology and selling equipment to partners. The company targeted utility-scale power generation and industrial process heat as its primary markets. This strategy attracted significant partners, including GE, NRG Energy, and Ferrostaal, and led to major licensing agreements, such as a deal with Penglai Electric to develop 2,000 MW of power in China. The company successfully demonstrated its technology with the 5 MW Sierra SunTower commercial plant in Lancaster, California, which supplied power to the Southern California Edison grid. Despite raising over $182 million from investors like Google.org and Oak Investment Partners, eSolar faced challenges as the market shifted favor towards cheaper solar photovoltaic (PV) technology. Reports suggest the company ceased business in late 2016.