By SCOTT HARRIS The Industry
Standard
HUNTINGTON
BEACH, Calif. - Like giant robotic sunflowers, the machines that
Boeing engineer Kenneth Stone has tended for nearly 20 years awaken
with the dawn.
Planted in
a sunny spot between a hangar and an office trailer on a Boeing
compound in this Southern California beach town, these shimmering
50-foot-tall solar dishes tilt their mirrored petals to the morning
glow. Through the day, they slowly pivot, tracking the sun's arc
across the sky, capturing, reflecting and focusing its rays to
power an attached engine that generates electricity.
In his mind's
eye, Stone sees vast, beautiful fields of solar dishes sprouting
in the deserts of the Southwest, converting sunlight into electricity
to power cities - without producing pollution, without accelerating
global warming.
Has Stone
been out in the sun too long? Not according to energy experts.
"This
isn't some mad scientist's mad dream. This is real," says
Terry Peterson, a solar market specialist with the Electric Power
Research Institute, a nonprofit research institute funded by the
power industry.
Solar is on
the brink of a breakthrough, its prospects brightening as the
nation's power crisis spurs investment in alternative energy by
municipalities, businesses and home owners. The mayor of sunny
San Diego, hit hard by soaring electricity prices last summer,
envisions the city's landfills covered with "solar farms"
that both harness the sun's rays and burn landfill gasses.
Up the coast,
San Francisco's supervisors are proposing a $100 million solar
bond to install photovoltaic panels on municipal properties. Meanwhile,
Fortune 500 powerhouses such as Bechtel, Boeing and Scientific
Applications International Corp. are pursuing a more ambitious
dream: bringing to market large-scale, centralized solar power.
Demonstration
projects are already running or being developed in Arizona, Nevada
and Spain.
Stirling Energy
Systems, a company that owns the dish technology that Boeing is
helping to develop through a U.S. Department of Energy contract,
has struck deals with utilities in South Africa and Spain for
test projects. "We're optimistic," Boeing project manager
Mike McDowell says of the technology that Stone has nurtured.
"We're trying to create a market."
Stone's specialty
is Stirling dish technology, one promising branch of the family
of renewable "solar thermal" energy sources. Although
most people equate solar energy with rooftop panels that produce
modest levels of wattage to help heat homes and run appliances,
solar thermal technologies are designed to provide power on an
industrial scale.
An early-generation
"solar trough" thermal plant built in the 1980s in the
desert near Barstow, Calif., generates five times the wattage
produced by all the solar panels in the United States. The system,
which generates 354 megawatts - enough to power about 350,000
homes - focuses the sun's rays to heat tubes filled with a synthetic
oil; the heated oil runs steam turbines to produce electricity.
Stirling dish technology is even more efficient at converting
the sun's energy into electricity, according to a Department of
Energy study.
Another solar
thermal technology, known as "power tower," is superior
to the trough as well. While less efficient than the Stirling
dish in converting the sun's energy to electricity, it possesses
a storage system that stretches power production beyond sunset.
Bechtel subsidiary Nexant is developing a massive power tower
project in the Spanish region of Andalucia. More than 1 square
kilometer of mirrors will focus the sun's rays to heat a tower
filled with tubes of molten salt. The heated salt stores energy
that powers electricity-producing generators.
So why has
the United States let these promising solar technologies languish
for two decades? The question is even more urgent considering
the international campaign to curb global warming caused by the
burning of fossil fuels. The answer lies in the geopolitics of
energy, the inconsistency of domestic power policies and the economics
of a volatile marketplace in the throes of deregulation. Shifts
in all these areas will determine the fate of solar development.
Scientists
have recognized the potential of Stirling technology for generations.
The Stirling engine is an external combustion engine, relying
on heat to cause hydrogen to expand and drive the pistons. Robert
Stirling, a Scottish minister, conceived of the closed-loop engine
in the early 1800s as an alternative to steam engines, which had
a lethal habit of blowing up. A French inventor later attached
a solar collector to a Stirling engine, according to Barry Butler,
a Scientific Applications International VP overseeing its energy
division.
Stirling engines,
he says, are now used in everything from submarines to prototypes
of artificial hearts used in animals. SAIC has developed a hybrid
Stirling dish that runs on sunlight during the day and burns landfill
gases at night to provide power. The company is in discussions
with San Diego about constructing solar power plants on its landfills.
The Stirling
engine remains buggy, and maintenance is a concern, experts say,
but technological advances make engineers optimistic about its
prospects. The Stirling engine is "about where the car engine
was in the 1950s," Stone says. "From a technology standpoint,
I don't see anything that would stop this. But so many political
things have stopped it before."
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