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Additional About Go Solar California Information

History of Solar Energy in California

Public domain picture of Alexandre_Edmond_Becquerel from Wikipedia

We can trace all energy used on our planet back to the source...the nearest star, our sun. The history of solar energy is as old as humankind. In the last two centuries, we started using Sun's energy directly to make electricity.

In 1839, Alexandre Edmond Becquerel (pictured on the right) discovered that certain materials produced small amounts of electric current when exposed to light.

William Grylls Adams, who, with his student, Richard Evans Day, discovered in 1876 that a solid material - selenium - produced electricity when exposed to light. Selenium photovoltaic cells were converting light to electricity at 1 to 2 percent efficiency.

Photovoltaic, or PV for short, is the word that describes converting sunlight into electricity: photo, meaning pertaining to light, and voltaic meaning producing voltage. It took, more than 100 years, however, for the concept of electricity from sunlight to become more than an just an experiment.

Birth of the PV Cell

Picture of three discoverers of solar cells

In 1954, D.M. Chapin, C.S. Fuller and G.L. Pearson, of Bell Laboratory, patented a way of making electricity directly from sunlight using silicon-based solar cells.

The next year, the Hoffman Electronics-Semiconductor Division announced the first commercial photovoltaic product that was 2 percent efficient, priced at $25 per cell, at 14 milliwatts each, or $1,785 per watt (in 1955 dollars).

By the mid-1960s, efficiency levels were nearing 10 percent. As an outgrowth of the space exploration in the 1960s-70s, PV development increased dramatically. But world wide hostilities and the threat of war turned the world more and more away from oil and toward renewable energy.

1970s & 1980s

In 1978, Congress passed the Public Utility Regulatory Policy Act or PURPA. It established the right for independent power producers to interconnect with the local utility distribution system. PURPA allowed large utility scale applications of PV and other solar electricity systems. Among other things, this federal legislation required utilities to buy electric power from private "qualifying facilities," at an avoided cost rate. This avoided cost rate is equivalent to what it would have otherwise cost the utility to generate or purchase that power themselves. Utilities must further provide customers who choose to self-generate a reasonably priced back-up supply of electricity. For small systems, such as a residential rooftop PV system, however, these protocols did not help the growth of small systems.

The Energy Tax Act (ETA) of 1978 (Public Law 9-618) was passed by Congress in response to the energy crises of the 1970's - the Arab Oil Embargo and the taking of U.S. hostages in Iran. The act encouraged homeowners to invest in energy conservation and solar and wind technologies through tax credits. A federal energy tax credit of up to $2,000 was given for devices installed on people's homes on or after April 20, 1977 and before January 1, 1986. Solar space and water heating carried a 40% tax credit, while weatherization, insulation, and similar conservation activities carried a 15% tax credit. However, the incentives were phased-out in the mid-80's as a result of Reagan administration policies to leave energy conservation and renewable energy decisions up to market conditions.

The federal tax credits, however, spurred the creation of new utility-scale solar and wind electricity systems. Wind turbines sprouted on California's windiest hillsides, and companies began investing in solar technologies.

picture of Solar One courtesy of DOE/NREL

In 1979, ARCO Solar began construction of the world's largest PV manufacturing facility in Camarillo, California. ARCO Solar was the first company to produce more than 1 megawatt (MW) of PV modules in one year. Four years later, ARCO Solar dedicated a 6 megawatt PV facility in central California in the Carrissa Plain. The 120-acre unmanned facility supplied the Pacific Gas and Electric Company utility grid with enough power for about 2,500 homes. ARCO Solar built a 1 MW PV power plant with modules on over 108 double-axis trackers in Hesperia, California.

Solar One began the first test of a large-scale thermal solar tower, power plant. Solar One was designed by the Department of Energy (DOE), Southern California Edison, Los Angeles Department of Water and Power, and the California Energy Commission. It was located in Daggett, California, which is about 10 miles east of Barstow.

Solar One's method of collecting power was based on concentrating the sun's energy to produce heat and run a generator. A total of 1818 mirrors, or heliostats, would track the sun across the sky and reflect the sun's light to the top of a large tower. A black-colored receiver, on top of the tower, transferred the heat to an oil heat-transfer fluid. The heated oil was then used to boil water, which turned turbines and generators. Solar One produced 10 MW of electricity. It was completed in 1981 and produced power from 1982 to 1986.

SMUD's 2-MW utility-scale photovoltaic power system co-located with the defunct Rancho Seco nuclear power plant. Photo courtesy of DOE/NREL, Warren Gretz In 1984, the Sacramento Municipal Utility District dedicated a 1.0 MW photovoltaic power plant to operate near the Rancho Seco Nuclear Power Plant south of Sacramento. That was later expanded to two megawatts.

In 1986, the world's largest solar thermal electricity facility began to be built in California's Mojave Desert. The LUZ Solar Energy Generating Stations (or LUZ-SEGS) contains rows of mirrors that concentrate the sun's energy onto a system of pipes circulating a heat-transfer fluid. The heated transfer fluid is used to produce steam, which powers a conventional turbine to generate electricity. All told, more than 300 megawatts of solar thermal electricity were built before the company had financial difficulties and was sold. They are still producing power today, 20 years later!

1990s to 2006

In 1993, Pacific Gas and Electric Company installed the first grid-supported photovoltaic system in Kerman, California. The 500-kilowatt system was considered the first "distributed power" PV installation.

1996, the U.S. Department of Energy and an industry consortium begin operating Solar Two - an upgrade of the Solar One concentrating solar power tower. Until the project's end in 1999, Solar Two demonstrated how solar energy can be stored efficiently and economically so power is produced even when the sun isn't shining; it also spurred commercial interest in power towers.

Another and more important event also occurred in 1996. Assembly Bill 1890 (Statues of 1996, Chapter 854, Brulte) was passed by the Legislature and signed by Governor Pete Wilson. This bill deregulated the state's investor-owned electric utilities and created incentives for grid-tied PV systems under the California Energy Commission's Renewable Energy Program. The following year, Senate Bill 90 (Statues of 1997, Chapter 905, Sher) implemented the provisions of AB 1890 and directed the activities of the Energy Commission relating to renewable energy.

picture of men installing solar panel to roof

The primary goal of this program is to develop a self-sustaining market for "emerging" renewable energy technologies in distributed generation applications. The Emerging Renewables Program (formerly called the "Emerging Renewables Buydown Program") was created to stimulate market demand for renewable energy systems that meet certain eligibility requirements by offering rebates to reduce (buy-down) the initial cost of the system to the customer. For systems larger than 30 kilowatts, the California Public Utilities Commission directed the investor-owned utility companies - Pacific Gas and Electric, San Diego Gas & Electric, Southern California Edison, and Bear Valley Electric - to work with businesses, governments and schools to install PV "self-generation" systems. In the ten years since 1996, more than 150 megawatts of electricity was installed through both the Energy Commission and the CPUC's programs. Nationally, the "Million Solar Roofs" program begun by President Bill Clinton in 1997 has supported the installation of 70,000 PV systems by the end of 1999.

In 2000, Senate Bill 1345 (Statutes of 2000, Chapter 537, Peace) directed the Energy Commission to develop and administer a grant program to support the purchase and installation of solar energy and selected small distributed generation systems. Solar energy systems include solar energy conversion to produce hot water, swimming pool heating, and battery backup for photovoltaic (PV) applications. Funding for the program had to be renewed annually by the Legislature. The state's budget crisis essentially ended the program.

In September 2000, the legislature adopted the Reliable Electricity Service Investments Act (RESIA) as the result of legislation: Assembly Bill 995 (AB 995, Statutes of 2000, Chapter 1051, Wright) and Senate Bill 1194 (SB 1194, Statues of 2000, Chapter 1050, Sher). These two pieces of legislation mandated the three investor-owned utilities to collect $135 million annually for 10 years beginning in 2002 to support the Energy Commission's Renewable Energy Program.

In 2001, during the height of the electricity crisis, Senate Bill 17xx - created a solar tax credit retroactive to January 2001. The tax credit, for tax years 2001-2003, was equal to the lesser of 15 percent of the net purchase cost of a photovoltaic or wind-driven system with a generating capacity of not more than 200 kilowatts. The Bill allowed credit for one system per each separate legal parcel of property or per each address of the taxpayer in California and required recapture of the credit if the system is sold or removed from California within one year. The credit was reduced to half that amount for tax years 2004-2005 and ended on January 1, 2006. Qualifying systems needed to be certified by the Energy Commission, installed with a five-year warranty, and would be required to be in service in California for at least one year. This bill complemented other programs that provided incentives for installing renewable systems.

Assembly Bill 29x in 2001 provided more funding to both investor-owned and municipal utility customers in the Energy Commission's Emerging Renewables Buy-Down Program. The additional funding came from state tax dollars (as opposed to ratepayer or "public goods charge" funding used by the deregulation bills). AB 29x also established a Renewable Energy Loan Guarantee Program, set up by the Technology, Trade and Commerce State Agency for larger renewable energy projects.

Senate Bill 1038 (SB 1038, Statutes of 2002, Chapter 515, Sher), signed in September 2002, incorporated the "RESIA Investment Plan" with changes. The bill directed the Energy Commission on how to implement the Renewable Energy Program from 2002 through 2006.

Signed by President Bush on August 8, 2005, the Energy Policy Act of 2005 (EPACT) offered consumers and businesses federal tax credits beginning in January 2006 for purchasing fuel-efficient appliances and products. Most of these federal tax credits remain in effect through 2007.

By 2006, the estimated yearly solar cell production reached 1,868 megawatts, and California made international news with the California Solar Initiative.