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SDG & E; Sees Sun Rise on Solar Firm

Before signing landmark energy legislation in New Mexico in August, President Bush got a peek at technology that soon could power San Diego.

When Bush addressed the crowd at the Energy Department’s Sandia National Laboratories, he stood before a wall-length banner, with fluffy clouds drifting across a deep blue sky. The placid scene was reflected at the bottom in two mirrored solar energy dishes.

The publicity may have been subtle, but on a day when all eyes were on the country’s energy policy, Stirling Energy Systems Inc. and its signature solar-energy dish grabbed a sliver of the spotlight.

A day later, Stirling generated its own headlines. The Phoenix-based company announced an agreement with Rosemead-based Southern California Edison to provide enough solar energy to power 278,000 homes.

Within a month, Stirling was back in the limelight, signing a contract with San Diego Gas & Electric Co. to provide enough solar energy to potentially power 180,000 homes during the daytime.

The deals represent landmarks for the privately held company , and the solar industry itself.

The two major projects would be the first large-scale solar plants built in more than a decade.

But some are skeptical, questioning whether Stirling is actually ready for prime time. Skeptics make this point: Six solar dishes functioning together , what Bush declared “fascinating” in August , is one thing.

Getting 12,000 dishes, which would generate as much electricity as a small power plant, to work reliably is another.

Stirling officials say they’re ready. But they know this, too: They still have work to do.

Vital Project

The Rev. Robert Stirling, a balding, white-haired Scottish clergyman, wasn’t thinking about the future of San Diego’s energy when he patented his namesake engine in 1816.

He was simply worried about the dangers posed by steam engines whose boilers had a tendency to explode.

Engineers have been adapting his technology ever since. Today, they’re used in submarines and auxiliary power generators.

Stirling Energy Systems has been developing its technology since the company formed in 1996, after buying the solar dish technology from SoCal Edison. The utility company had originally purchased the Stirling technology from McDonnell Douglas, but abandoned the project when deregulation took effect.

Here’s how the engine works in solar applications: The sun’s rays hit the dish. Mirrors reflect them into a central collector.

The sun’s heat, now focused, warms hydrogen in the engine. The gas expands and churns the engine’s pistons.

Voil & #341;. Electricity.

By 2010, Stirling is supposed to supply the San Diego region with that solar energy.

SDG & E; is counting on it. That’s when the local utility has said it will meet a state goal of getting 20 percent of its energy from renewable sources.

As a sign of this technology’s importance, SDG & E; cites its plan with Stirling as a justification for building the Sunrise Powerlink, a power line stretching from the sun-baked Imperial Valley into San Diego. The controversial plan would cost consumers $1 billion.

SDG & E; has intertwined the Stirling project’s fate with the Powerlink’s approval. The solar project is contingent on the Powerlink, SDG & E; has said in filings with the California Public Utilities Commission.

Though the financial terms of its contract with SDG & E; are confidential, Stirling is shouldering most of the risk. If the technology never materializes, SDG & E; won’t take any financial loss.

“There’s minimal risk for the utility,” said Bob Liden, Stirling’s executive vice president. “Their risk is that if we don’t deliver and they miss the (renewable energy) goals, they may have some significant penalties there. The risk is more clearly on our side.”

When pressed, Liden corrected himself on one point. If Stirling doesn’t deliver and SDG & E; misses the 20 percent renewable goal, the state has adopted no penalties.

Problems Remain

Look at Stirling’s Web site, and you won’t detect any hint the engine still needs work.

According to the site, Stirling’s solar technology has finished research and development and is ready for large-scale deployment.

Liden said the information is correct and that research and development will only continue “incidentally.”

But Stirling must still clear several obstacles before it provides energy.

SoCal Edison is requiring the company to build a one-megawatt test facility in the Mojave Desert to prove its reliability.

And Stirling admits it still has a problem with a vital engine seal, which leaks hydrogen , its very lifeblood.

“It’s a problem, but I’m not sure it’s a showstopper,” said Frank Wilkins, the Energy Department’s solar thermal team leader. “It would seem to me that it can be done. It’s a question of whether you can solve it in the time frame” the utilities have set.

Significant challenges still linger, Wilkins said. He points to the Mojave test site, which Stirling officials hope to have running by early 2007, as an important litmus test.

The site will test 40 solar dishes, the first jump from the six that President Bush saw. The project will help Stirling officials determine failure rates, Wilkins said.

“The engine has to work reliably for five years or 10 years,” said Fred Morse, a former Energy Department official who ran solar research under Presidents Carter and Reagan. “While it’s easy to pull one out and put in a new one, you can go broke doing that.”

Some familiar with the solar technology question whether Stirling will be able to solve its problems by 2010, when the projects are due on-line.

By then, Stirling expects to have chosen a 3-square-mile site in the Imperial Valley, east of San Diego, and have built 12,000 solar dishes for the SDG & E; project.

“Going from (six dishes) to a commercially viable business I think is going to require one hell of a lot of resources,” said Herb Hayden, solar program coordinator at Arizona Public Service, the state’s largest investor-owned utility. “It’s going to be a whole different reality.”

Hayden and his team studied several types of Stirling engines in the 1990s , then concluded the technology wasn’t reliable enough.

“These six dishes (in New Mexico) are the first ones running,” Hayden said. “They’re running. I give them credit for that. But they’re not commercial. They’re prototypes.”

Solar Resurgence

Renewable energy advocates see positives in the Stirling-SDG & E; contract.

It’s a sign utility companies understand concentrated solar energy , still in a pioneering phase , will only work on a large scale, said Michael T. Eckhart, the president of the American Council on Renewable Energy, a Washington, D.C.-based industry advocacy group.

“Only at that scale do the economics start to work,” Eckhart said. “They’re in effect giving the technology the best possible chance. Now it’s up to the private sector to live up to their claims.”

The Stirling project is part of a larger resurgence of solar energy. For more than a decade, no new solar projects have been built in the United States.

The country’s only major source of large-scale solar , using a technology known as a “parabolic trough” , was built in the 1980s in Kramer Junction, Calif., by an Israeli company.

Government subsidies made the expensive project possible.

Now the solar industry is poised to rebound, Fred Morse said.

Natural gas-fired power plants, once the least expensive way to generate electricity, are seeing costs surge. Rising natural gas prices are narrowing the gap with more expensive solar energy.

With utilities in California, New Mexico, Arizona and Nevada trying to meet renewable energy goals, Morse said the economy is slowly swinging in favor of solar.

And Stirling is poised to capitalize on it. But the firm has to get everything right, Morse said, and the company’s investors need deep pockets if troubles arise at the Mojave test site.

Stirling officials remain confident, and say they know what’s at stake.

“If we for some reason were not to succeed, it’d be a pretty dramatic failure,” said Stirling’s Liden. “If we do succeed, we have an enormous opportunity to deploy this technology in most every solar-rich area of the world.

“This is a big deal for us.”


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