Solar's day in the sun -- Two BIG Dish-Sterling Solar Power
http://www.post-gazette.com/pg/05321/607999.stm
Solar's day in the sun?
Thursday, November 17, 2005 By Rebecca Smith, The Wall Street Journal
Ambitious plans to cover two big swaths of California desert with solar dishes could finally help the energy-producing technology make the leap to industrial-scale development.
Stirling Energy Systems Inc., of Phoenix, hopes to construct 20,000 solar dishes covering four square miles of the Mohave Desert near Victorville, Calif., each dish pointing skyward to collect the sun's energy and convert it into electricity that would flow 80 miles south to power-hungry Los Angeles. The solar encampment, if eventually built, could produce 500 megawatts of electricity, enough to meet the daytime needs of 300,000 homes, doubling the state's solar capacity. The project cleared a hurdle last month when state regulators approved a 20-year power-purchase agreement between Stirling and Southern California Edison, a unit of Edison International.
A second project, involving Stirling and San Diego Gas & Electric Co., a unit of Sempra Energy, awaits approval. It calls for the purchase of 300 megawatts of solar power from a Stirling project in the Imperial Valley, east of San Diego, with an option to expand to as much as 900 megawatts -- the equivalent of two big gas-fired power plants.
The agreements, whose financial details haven't been disclosed, come as California has deepened its resolve to make more electricity from renewable sources, in part because of skyrocketing natural-gas prices after recent hurricanes along the Gulf Coast and also as a result of electricity blackouts in the state last summer. Another factor: Rising electricity prices are emboldening utilities to gamble on somewhat experimental technologies.
What is needed now is large-scale manufacturing of solar dishes to drive costs down, says Robert Boehm, director of the Center for Energy Research at the University of Nevada at Las Vegas. A hot zone, stretching from California to western Texas, looks ideal for "sun concentrating" technologies that need strong, direct sunlight to work well. In contrast, photovoltaic technology, found in rooftop solar panels, can make electricity under cloudy skies but isn't suited to powering whole cities.
The biggest challenge facing Stirling is to move its technology to mass production, says the company's chief executive, Bruce Osborn. To date, Stirling has made fewer than a dozen dishes, mostly for demonstration projects. Based on his two decades of experience in high-volume manufacturing and project management at Ford Motor Co., Mr. Osborn is confident the obstacles can be overcome.
If the two big projects are successful, they are likely to inspire more utility-scale solar projects elsewhere in the arid Southwest, where the population is growing rapidly. They would help solar energy take an important step foward, much like what happened in the early 1900s to the conventional power industry when it went from tiny generators supplying power to single sites to "central station" plants furnishing juice to thousands of customers.
This is the second time California has tried to make this jump. Following the energy crisis of the late 1970s, Israel-based Luz Solar Partners Ltd. built a 365-megawatt installation based on a type of solar-concentrating technology called a "parabolic trough." The project, nine units installed from 1984 to 1990 near Barstow, Calif., subsequently went through other hands and then faced financial failure in the late 1990s, when federal subsidies expired. Today, a unit of FPL Group Inc., based in Juno Beach, Fla., operates a majority of the units and sells the power to Edison under long-term contracts.
For 20 years, "solar power" has meant photovoltaic panels, like the ones found on homes in the Sunbelt states and on flat rooftops in states, like New Jersey, with policies favoring renewable power. Costs have come down dramatically as manufacturing methods have improved and volumes have grown.
But the industry has struggled in the years since the Reagan Administration, when Congress drastically reduced tax credits and subsidies. The U.S., which was manufacturing half of all photovoltaic panels as recently as a decade ago, now supplies only about 8 percent globally, as policies favoring renewable power in Japan, Germany and other countries have boosted production there.
The U.S. solar industry appears poised for a rebound, with the passage last summer of the Energy Policy Act, an omnibus energy bill that restored residential tax credits for solar installations and boosted federal support for commercial projects to levels not seen in decades.
It is difficult to compare the economics of electricity produced from photovoltaic panels versus that from solar dishes. That is because solar-panel electricity is made in small amounts and mostly is consumed on-site. Solar dishes, by contrast, make large sums of electricity, at least in theory, and it is put directly on the transmission grid, like other big power plants. It is wholesale power, not retail power.
The hope is that solar dishes will one day make electricity for less than 10 cents a kilowatt hour, which is about what it costs to make electricity at modern, gas-fired power plants at today's fuel prices and less than half the cost of making it with photovoltaic panels.
Solar dishes hold the promise of being cheaper to build, maintain and operate than any other earlier form of solar power. Curved mirrors lining the inside surface of a Stirling dish focus sunlight on a receiver suspended above. Inside the receiver is a tank of hydrogen gas. When the gas heats, it expands and drives an engine, which in turn operates a generator to make electricity. John Bryson, Edison's chairman, said he was attracted to Stirling's technology because, "at least in the lab, it increases efficiencies to twice what we'd seen" from other solar technologies.
Edison once had rights to some of the technology that Stirling now is commercializing. Edison was a leader in solar development in the 1980s but abandoned the area when interest waned and the state began its march toward electricity deregulation in the early 1990s. In 1996, Edison sold its solar interests to Stirling for a "few hundred thousand dollars," according to Mr. Osborn. He said no Edison executives or managers are investors in his firm.
Sempra officials, meanwhile, acknowledge the risks of relying on dishes that haven't been proven commercially feasible. But one of California's policy goals "is to have utilities enter into contracts that are helpful to making new technologies economic," says Terry Farrelly, a Sempra vice president of energy procurement. California's goal is to obtain at least 20 percent of its electricity from renewable sources by 2010, up from the current level of about 12 percent. In June, Gov. Arnold Schwarzenegger announced he wants the state to achieve a 33 percent target by 2020.
Utilities in other states have been nudging big solar projects forward, too. Sierra Pacific Resources, of Reno, Nev., has been working with Solargenix Energy, based in Raleigh, N.C., and formerly Duke Energy's solar-power unit, to get a 55-megawatt project built in Nevada. Arizona Public Service, a unit of Pinnacle West Capital Corp., is working on half a dozen solar technologies including one that would use solar dishes to heat air, not hydrogen, to run a turbine. "We love the idea of a dish and think it's no more complicated than a car," says Peter Johnston, head of APS's research effort.
In addition to manufacturing hurdles, other challenges remain. Dishes need a lot of land, so anything that pushes up land prices or raises environmental concerns could hurt their prospects. And they need big transmission lines to get the power to users. Nevertheless, some solar-power advocates think this is the best time in nearly 30 years to push for large-scale development. Says Doug Faulkner, an assistant secretary in the U.S. Energy Department: "Things are starting to line up."