World’s biggest solar PV tracking plant completed in US

Construction of the world’s largest single-axis tracking solar PV plants – the 206 MW Mount Signal Solar farm in south east California – has been completed and is ready to generate enough electricity to power 72,000 households in San Diego and surrounds.

The project – constructed and commissioned in a record 16 months by Spanish multinational Abengoa, for Silver Ridge Power – covers 801 hectares and includes more than three million photovoltaic modules that will rotate on a north-south axis, following the path of the sun. This will help lift the output from the plant.

Based in Virginia US, Silver Ridge Power (formerly AES Solar) is one of the world’s largest photovoltaic owner-operators, with a stake in 51 utility-scale PV plants totalling around 522MW in operation or under construction in seven different countries around the world.

Notably, the Mount Signal project attracted a $103 million investment from Google in October last year, the technology company saying that the renewables investment (the company’s thirteenth, at the time) reflected its “strong belief” that backing clean energy technology made business sense.

Sun tracking solar technology enable solar PV modules to remain in the best position to accumulate maximum energy from the sun. In Australia, the largest example of the technology is a 340 panel array on top of a steel products factory in Melbourne’s south-east.

As we reported here in October, when the rooftop solar farm on Hilton Engineering’s 15,000 square metre factory was first switched on, the solar trackers allow the 98.6kW array to generate up to 40 per cent more energy than normal stand-alone panel.

Tracking technology is also used in solar-thermal tower technology – Abengoa’s specialty – to move the mirrors that focus the reflected solar radiation onto a central tower where the heat is transferred to molten salts, to water, creating superheated steam which drives a turbine.

Most recently, Abengoa won a contract to build a 110MW solar tower project with storage in Chile, the first of its type in Latin America. The project will have 17.5 hours of storage through the use of molten salts and, given its sundrenched location, should be able to provide power without interruption if required.