What percent of California power is made by solar panels?
A decade ago, only 500 rooftops in California boasted solar
panels that harvest the sun's energy. Today, there are nearly
50,000 solar-panel installations in the state, according to a
report to be issued Thursday by the research and lobbying group
As a result, California, the longtime national leader in solar
energy, has a capacity of more than 500 megawatts of solar power at
peak periods in the early afternoon --- the same as a major power
The solar capacity in California grew by a third from 2007 to
2008. It now represents about two-thirds of the national total,
according to a different report that is being prepared by the
Interstate Renewable Energy Council, a nonprofit group promoting
expansion of solar energy.
As the Obama administration pushes for a national shift to more
renewable energy sources, California's example is therefore being
closely watched. Nationally, the states in which solar
installations are spreading fastest are those that provide the most
generous subsidies for them, industry experts agree.
Two long-term statewide programs in California provide rebates
and other financial incentives to encourage rooftop solar panels,
and individual municipalities like Berkeley are also beginning to
offer financing for the solar arrays.
"The thing about California is that they have a consistent
program that has 10 years of funding," said Larry Sherwood, a
consultant to the interstate council.
(The California budget cuts that were being brokered Wednesday
will not directly affect the subsidies because the subsidies are
underwritten by utility ratepayers, not taxpayers.)
New Jersey is a distant second to California in installed solar
capacity with 70 megawatts, followed by Colorado and Nevada, the
council's report said.
The Clean Energy program in New Jersey offers qualifying
residential and commercial customers rebates for energy generated
by solar arrays.
"Typically, New Jersey incentives have been higher, but its
program has had many fits and starts," Mr. Sherwood said.
Within California, solar technology has spread beyond highly
environmentally conscious areas like San Francisco and Sacramento
over the last decade to gain a hold throughout the state,
Environment California's report indicates. As of the end of 2008,
when the report's figures were compiled, San Diego had more than 19
megawatts in capacity from installations on 2,200 roofs, followed
by San Jose with 15.4 megawatts from 1,330 roofs and Fresno with
14.5 megawatts from 1,028 roofs.
"The biggest thing here," said Bernadette Del Chiaro, the
report's author, "is that from farms to firehouses, the face of
solar power is changing. While California's biggest cities have led
the way, the rest of the state and country are quickly picking up
She added that the cities of the Central Valley, which is both
heavily agricultural and baking hot in the summer, are natural
places for the solar panels. High air-conditioning loads and high
peak electricity rates tend to dovetail partly with the afternoon
hours when solar panels are most effective, she noted, giving
people an incentive to embrace the new technology.
Nationally, residential installations account for about a third
of the energy supplied to the power grid by photovoltaic arrays on
panels; the remainder come from installations on larger facilities,
like government buildings, retail stores and military
Each of the four top-ranked cities in California in terms of
solar power capacity have more electricity available from these
sources than all but six states.
Still, 10 states, led by Colorado and including Hawaii,
Connecticut, Oregon, Arizona, North Carolina, Pennsylvania and
Massachusetts more than doubled their rooftop solar capacity in
2008, Mr. Sherwood said.
While most installations are on rooftops, the number of
larger-scale installations is increasing. Fresno's total output is
augmented by a 2.4-megawatt facility at the Fresno Yosemite
International airport, while the local Sierra Nevada brewery in
Chico has a 1.9-megawatt solar array.
Outside the state, Nellis Air Force Base in Nevada has the
largest photovoltaic generating plant, with 70,000 panels
generating 14 megawatts of electricity, according to the federal
Energy Information Administration.
But even with the increases of the last decade, solar power is a
pipsqueak among energy sources; it represents about one-quarter of
1 percent of California's total energy capacity, according to the
California Energy Commission. Nationally, according to the Energy
Information Administration, it represents about 0.02 percent of
total capacity, but those federal figures are incomplete: they
reflect only centralized facilities, not distributed rooftop
Cost is a major hurdle; installation of a rooftop system is
likely to cost at least $20,000.
In other countries, according to the Renewable Energy Policy
Network for the 21st Century, a research and advocacy group,
government subsidies have led to rapid growth in solar power. The
group's latest report shows Germany as the world leader in solar
power, with 5,400 megawatts, or about 1 percent of the country's
total generating capacity.