A unit of Spanish conglomerate Abengoa has gotten the final sign-off on the U.S. Department of Energy's largest renewable-energy loan to date, a $1.45 billion loan guarantee for a 250-megawatt solar thermal power plant in Gila Bend, Ariz.

The loan guarantee helps advance the nation's broad goals of building up renewable energy resources and lessening its dependence on fossil fuels.

This year, regulators have approved several large-scale renewable energy plants in the Southwest, but many of them haven't yet lined up financing.

An Abengoa Solartower in Europe.

With the loan guarantee, which was announced on a preliminary basis in July, Abengoa Solar will be able to start construction on its Gila Bend plant, which at 250 megawatts will be big enough to power at least 75,000 homes.

The size of Abengoa's DOE loan guarantee tops one awarded to BrightSource Energy, which has a conditional loan guarantee for $1.37 billion to support its 370-megawatt Ivanpah plant in California.

Abengoa's Solana plant will use parabolic trough technology, meaning arrays of mirrors will collect energy from the sun and use it to heat fluid. The fluid will power steam generators that produce electricity. The plant will store electricity using a molten-salt technology.

The project should generate some 1,600 to 1,700 construction jobs, and about 80 operational jobs upon completion. Pinnacle West Capital's Arizona Public Service utility unit will purchase Solana's output.

Abengoa also has a 250-megawatt parabolic-trough plant under development in California's Mojave Desert.

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