206MW Mount Signal reaches finish

Construction has wrapped up at Silver Ridge Power’s 206MW Mount Signal Solar array in Calexico, California, bringing to an end a multi-year development and construction process which saw the project flip from Stirling Dish CSP technology to PV.

Initially known as Imperial Valley Solar 1, Mount Signal was part of a 700+MW proposed series of projects on federal land owned by now-bankrupt developer Tessera, which was ultimately brought to its knees (alongside sister company Stirling Energy Systems) by financial and legal challenges.

AES Solar – a solar-energy joint venture owned by power giant AES and the private-equity firm Riverstone Holdings – acquired the projects in 2011, and brought on co-developer 8minutenergy.

AES Solar has since been renamed Silver Ridge Power.

In 2012, Spain’s Abengoa won an EPC contract worth $365m to build Mount Signal, which uses more than 7 million PV modules attached to trackers following a north-south axis, and employed more than 700 workers in California's Imperial Valley at peak construction.

The deal further consolidated Abengoa’s strong presence in the booming US utility-scale solar business, having won major EPC work on both the PV and CSP side.

Mount Signal is the world's largest PV plant to use single-axis trackers, and among the largest in the world, full stop.

Electricity produced at Mount Signal is sold to San Diego Gas & Electric Company. Google invested $103m in the project late last year.

With Mount Signal on line, Silver Ridge, based like co-parent AES Corp. in Arlington, Virginia, owns more than 520MW of operational utility-scale PV capacity – with one of the world’s most geographically diversified portfolios, spanning the US, Puerto Rico, Europe and India.

AES Corp. is among the largest US-based power generators, with 29GW of installed capacity around the world – nearly one-third of it renewables. Among the wind farms owned by AES is Buffalo Gap phases 1-3, in west central Texas, which tips the scales at 524MW.