FOR IMMEDIATE RELEASE PHOTO AVAILABLE

RECORD-BREAKING $2.3 MILLION ALTERNATIVE ENERGY REBATE PRESENTED TO SOLAR WASTEWATER TREATMENT PLANT

PG&E Gives Rebate to Sewerage Commission-Oroville Region for Solar Array

OROVILLE, CALIF. (April 30, 2003)–The Sewerage Commission-Oroville Region (SC-OR) announced today that its wastewater treatment plant, powered by a 520 kilowatt solar system, received an alternative energy generation rebate check of $2,342,000 from PG&E, the largest renewable energy system rebate in PG&E history.

The rebate was presented to SC-OR Superintendent Ray Sousa by Anlin Ting-Mason, vice president of PG&E's Internet and Energy Program Services, during a dedication ceremony on Earth Day, April 22, at the SC-OR plant in Oroville, Calif.

The rebate helps to pay down SC-OR's costs for installing the 520 kilowatt solar electrical system, one of the largest solar arrays in the U.S. The rebate is from PG&E's Self-Generation Incentive Program, funded by ratepayers under a mandate by the California Public Utilities Commission to encourage alternative energy. The total cost of the solar system was $4,825,116 before the rebate.

SPG Solar, Inc. (SPG) headquartered in San Rafael, Calif. engineered and built the SC-OR solar array, which was commissioned and went online in November 2002. The solar array generates the equivalent of the energy needed to supply 200 homes. By using sunlight to supply its own electricity, SC-OR frees this energy for use during the day by other electric customers connected to the public utility grid.

SC-OR's 60-acre wastewater treatment plant runs 24/7/365 and has a mission-critical need for a stable power source. It serves 15,000 families and numerous industries in the greater Oroville area, and is designed to treat 6.5 million gallons of wastewater a day.

The solar array covers three acres adjacent to the wastewater treatment plant, and consists of 5,184 solar panels connected by 110,000 feet of wiring, nearly 20 miles of wire.

SC-OR is the first solar-powered wastewater treatment in the U.S., and has become a model of energy self-generation for public works projects around the world. It is the largest dual-tilt solar array in the world, the fifth largest solar system in California and among the top ten largest in the U.S.

In 2001 California experienced rotating power outages following rapidly rising wholesale energy prices. Over the two years prior to 2001 SC-OR saw its energy costs skyrocket by 41 percent. Normally, electric bill increases would be reflected in higher sewer bills. In this uncertain energy environment, SC-OR Superintendent Sousa investigated alternative energy sources that would stabilize his energy supply and reduce his electric bill.

"We checked into renewable energy, focusing on solar, and found the PG&E incentives program on the Internet," said Ray Sousa. "With the solar system, which provides 80 to 90 percent of the energy we need, we stabilized our electric supply so we don't have to pass rate increases on to our customers."

"PG&E's commitment to solar power and renewable energy has never wavered and we are proud to have partnered with the Sewerage Commission-Oroville Region on this important project," said Anlin Ting-Mason of PG&E. "We are very pleased about the positive impact this rebate will have on Butte County's economy and the environment."

Oroville Mayor Gordon Andoe proclaimed Oroville "Solar City USA" at the SC-OR Earth Day event. One of the most completely solar-powered municipalities in the nation, Oroville is currently installing solar systems on City Hall, the Police and Fire Headquarters, the City Maintenance Yard, the Pioneer Museum, and the city-owned State Theater. All the Oroville civic solar installations, designed and under construction by SPG, will be commissioned by June 1.

Net Energy Metering
SC-OR is tied to the utility grid. SC-OR runs 24/7/365, and at night or on rainy days, when it needs more electricity than the solar array can generate, it takes power from the grid. The solar system generates up to 520 kilowatts of electricity while the sun is shining, more energy than the plant needs during the day. Under PG&E's Net Energy Metering Program, SC-OR earns credit for sending excess power back to the grid.

On sunny days the electric meter runs backwards and PG&E credits SC-OR for the power it receives from the system. At night and on rainy days, SC-OR taps into the credit it earned with PG&E. At the end of the year the combination of solar power and credits for solar energy production will slash SC-OR's electric bill by over 80%.

"The success of the SC-OR array is a proof of concept of Net Energy Metering and PG&E's incentives program," said Dan Thompson, president of SPG. "Each California electric ratepayer contributes to the alternative energy rebate fund. Each Californian benefits because SC-OR relieves pressure on the grid, plus it replaces traditional power generation with clean solar energy."

"It's nice to sit at home at night and know that SC-OR is running on the energy it overproduced during the day," said SC-OR Superintendent Ray Sousa.

Dual Tilt
The dual-tilt mounting system for the SC-OR solar array was developed by SPG's President, Dan Thompson. The 5,184 solar photovoltaic panels are mounted on steel supports in rows on the ground. In the spring, summer and fall the panels rest on the supports at a 10-degree angle to maximize their exposure to the sun while it is highest in the sky.

In the winter, when the sun sinks low in the sky, each panel is tilted up to a 30-degree angle for greater exposure to sunlight. Each solar panel is hinged at the bottom. A crew tilts up each panel manually and locks it into place with a pin. This appropriate technology maximizes the solar array's sunlight exposure without expensive, high maintenance sun-tracking machinery.

How Solar Works

Solar energy systems consist of three components: PV panels, inverters and a performance monitor. PV panels convert sunlight into DC (direct current) electricity. The inverters change the DC into AC (alternating current), the same power supplied by electric utilities. The AC is distributed through a building's electric service panel and flows to outlets, lights and switches. The performance monitor shows the amount of power the system is generating at any time to verify production. Solar is a clean and renewable form of electricity generation. PV systems generally have no moving parts (with the exception of solar tracking systems), is silent, runs all the time while the sun is shining, and produces zero emissions-air, ground or water.

About SPG Solar, Inc.

SPG is the industry's most experienced developer, designer, and installer of solar photovoltaic (PV) systems for homes, businesses, and large-scale commercial and government facilities. SPG's commitment is to build the highest-performing solar PV systems with the highest return on investment. The result is clean, reliable electricity that reduces or eliminates customers' electric utility costs. SPG has installed over 500 solar systems in California, including the Potrero Hill Head Start in San Francisco, and Westmont High School in Campbell, California. Major projects include the Vallejo Police and Fire headquarters, Vallejo, Calif., and the 520 kW system for the Sewerage Commission-Oroville Region. SPG is a licensed and bonded California General B, Solar C-46 and Electrical C-10 Contractor, License #759086.