Place to put facility yet to be determined
Sep 8, 2005 - Craig D. Rose - Union-Tribune
San Diego Gas & Electric announced yesterday it had contracted
with a Phoenix company to buy electricity from what
could be the largest solar power generating project
in the world.
A Stirling Energy Systems
installation at Sandia National Laboratories
in Albuquerque, N.M. The technology uses mirrors
that direct the heat of the sun onto a central
The generating facility will be among the first to use
a new solar technology said to double the efficiency
of other approaches and initially generate up to 300
megawatts of electricity, enough to power nearly 300,000
SDG&E and Stirling Energy
Systems, the Phoenix company building the project,
say there is also an option to expand the project
to 900 megawatts. The project will be located somewhere
in the Imperial Valley desert - an exact location
has not been decided - and begin producing electricity
in 2008, with completion set for 2012 if the expansion
option is fully exercised.
The proposal must be approved
by the California Public Utilities Commission to proceed.
Rhone Resch, president of
the Solar Energy Industries Association, said that
Stirling announced an 850-megawatt project last month
using the same technology with Southern California
Edison. The SDG&E and Edison projects combined
would roughly triple U.S. solar electric generating
capacity, he said.
"This is a huge milestone
for solar," Resch said. >
He added that the projects
could create economies of scale and drive down costs
to the point where solar concentrating technology
could be economically applied on a smaller scale.
James Avery, a senior vice
president of SDG&E, said the first phase of the
solar project planned for Imperial County would boost
the percentage of electricity the local utility derives
from renewable sources to 9 percent, up from 5.5 percent
If the project is expanded
to 900 megawatts, SDG&E's renewables would rise
to 17 percent of its total generating capacity.
Stirling's technology uses an array of mirrors that
direct the heat of the sun onto a central engine.
The engine's dual pistons move in response to heating
and cooling and drive a generator. The so-called solar-thermal
technology was developed in federal laboratories and
has been demonstrated at a handful of locations in
the United States and abroad, the company said.
Bruce Osborn, chief executive
of Stirling, said the improved efficiency lowers the
cost of producing electricity to new levels.
"So no state price supports
are needed," Osborn said.
The SDG&E project will
require about 12,000 of the Stirling engine clusters,
covering about 3 square miles in the desert.
To transmit the electricity
generated to customers in San Diego, SDG&E said
it would be necessary to build a new power link across
the desert, a 1,000 megawatt transmission line that
the utility previously said it was planning.
The local utility is required by state law to obtain
20 percent of its electricity from renewables by 2017.
But SDG&E says it hopes to reach a goal of 20 percent
renewables by 2010 set by the PUC.
Financial details of the
solar generating project were not announced yesterday,
but Avery said that the economics of renewable energy
"We have been able to negotiate
a price that is competitive with electricity generated
from fossil fuels," Avery said. "We used to pay a
10, 20 or even 30 percent premium for renewables in
At least a part of that shrinking differential is
because of the soaring cost of fossil fuels, in particular
natural gas. The cost of natural gas, the primary
fuel generating electricity in California, has more
than doubled in the past year.
The executive director of
a local utility watchdog group said he welcomed the
"This is a good project,"
said Michael Shames of the Utility Consumers' Action
Network. "This is a worthwhile technology and a good
Shames added, however, that
the solar project location was flexible and that it
could be serviced by a more modest new power link
than the one proposed by SDG&E. The larger new
transmission line proposed by the local utility, Shames
said, would serve the needs of Sempra Energy –
SDG&E's parent company - more than local
The consumer group says the
proposed major transmission project, which would be
paid for by utility customers, would allow Sempra
to move electricity from plants it has in Mexico and
Arizona to areas north of San Diego, broadening the
market for that power.
But SDG&;E says the power
line it proposes would primarily benefit the 1.3 million
consumers it serves in San Diego by providing access
to cheaper sources of electricity and improving reliability.