Too late for Big Solar to save the day?

California utility PG&E on Tuesday announced contracts to buy up to 900 megawatts of electricity generated by solar power plants to be built in the Mojave Desert by BrightSource Energy. It’s one of the biggest solar deals to date -- enough to power some 600,000 homes -- and is another sign that that the shift from fossil fuels to carbon-free energy is well underway, at least in California.

But is it too late? PG&E (PCG) first announced it was negotiating a power purchase agreement with BrightSource, then called Luz II, on Aug. 10, 2006. Around that time, the United States’ leading climate scientist, NASA’s James Hansen, warned that the world had only a decade to take drastic action to cut carbon emissions and avert a global catastrophe from global warming.

It took nearly two years alone to just hammer out the PG&E-BrightSource deal and the world now has eight years left to radically ramp up alternative energy sources. By the time the first BrightSource 100-megawatt solar power plant (image above) goes online it will be 2011 and the last one will begin generating electricity for PG&E just as the climate change alarm clock goes off. If you believe Hansen, hitting the snooze button will not be an option.

Of course, there’s no guarantee the BrightSource plants will actually be built — it will take billions to construct them and the investment climate is not exactly sunny these days, clouded by Wall Street’s meltdown and the looming expiration of a crucial solar investment tax credit. (Personally, Green Wombat is betting BrightSource pulls it off — though April Fool’s Day probably was not the best date to unveil such a deal. The Oakland, Calif.-based company was founded by solar pioneer Arnold Goldman, its CEO, John Woolard, hails from Silicon Valley and the startup is backed by Morgan Stanley (MS) and some savvy venture capitalists.)

Given the moral and regulatory imperative — California utilities must obtain 20 percent of their electricity from renewable sources by 2010 and a third by 2020 — why is large-scale solar proceeding at the pace of a Mojave Desert tortoise? (Almost three years ago, for instance, Southern California Edison (EIX) and San Diego Gas & Electric (SRE) unveiled agreements with Phoenix’s Stiring Energy Systems to buy up to 1,750 megawatts of solar electricity. Ground has yet to be broken on any of the planned power plants.)

Partly it’s because the years-long negotiations between utilities and solar power plant companies is something of a black box. Details of these power purchase agreements are kept confidential but are estimated to be worth billions — if a recent $4 billion dealstruck by utility Arizona Public Service with solar power plant builder Abengoa Solar is any indication. Regulated utilities are by their nature big and bureaucratic and can be expected to be extra-cautious when they’re placing bets on untried solar technology from companies like BrightSource and Ausra.

“Transactions of this magnitude require a fair amount of time to negotiate and due diligence must also be performed,” PG&E spokeswoman Jennifer Zerwer told Green Wombat in an e-mail. “The original [BrightSource agreement] announced in August 2006 was for 500 megawatts; the final agreement expanded on the original . . . and culminated in the execution of five separate power purchase agreements for up to 900 MW.”

Another factor is a regulatory structure that is an artifact of the fossil fuel age. California requires extensive environmental review of new power plant projects — be they clean and green or down and dirty — a process that can take a 18 months or more. And the best solar sites often are on federal land in the Mojave — securing a lease for that land is another 18-month-long process.

Still, when the United States faced a threat of a different kind in World War II, it retooled its factories in a matter of months to produce planes and tanks. The fight against global warming will require a similar agility.

The clock, after all, is ticking.