The Propane Education & Research Council joined the University of California Davis, Onsite Power Systems Inc., and industry partners last week at the official start-up of the anaerobic biodigester system for UC Davis' Biogas Energy project.

The project will demonstrate an innovative waste-to-energy technology with possible environmental and economic advantages, including potential as a renewable energy source.

"The event was a celebration," said Dave Konwinski, CEO of Onsite Power Systems Inc., and project manager for the UC Davis biodigester. "We wanted to share this exciting demonstration with our sponsors, the media, and the public."

The Biogas Energy project, the idea of UC Davis professor Ruihong Zhang and students in the biological and agricultural engineering department, began with eight years of university lab tests and engineering by Onsite Power Systems, before being presented in June to members of the governor's office and to French Polynesia President Oscar Temaru of Tahiti.

Biodigesters often need supplemental power for start-up, shutdown, and other purposes to ensure uninterrupted operation. To meet this need, PERC contributed to the purchase of two propane-fueled boilers; a low-emission, California Air Resources Board-certified propane engine; and a generator for the project.

"In light of Gov. Schwarzenegger's recent focus on going green, the biodigester is an exciting new technology with some promising environmental implications," said PERC Director of Agriculture Programs Mark Leitman. "Biodigesters could provide a new renewable energy source, especially for the agricultural market, so PERC is honored to be a sponsor of this groundbreaking research."

Anaerobic biodigesters use bacteria to break down animal waste, plant material referred to as green waste, and food waste and convert it to biogas, a form of methane. The UC Davis/Onsite Power Systems biodigester also produces raw hydrogen in its two-step process. The hydrogen can be marketed as a fuel source for use in fuel cells or motor vehicles and sold as an industrial product. The biodigester can produce an estimated 22 therms of high-quality biohydrogen and biogas from one ton of food waste or green waste.

Propane-fueled boilers aid in biodigestion

The Biogas Energy project's biodigester uses the propane-fueled boilers donated by PERC to sustain internal heat at the required temperature to promote optimal bacteria growth to produce the most efficient natural breakdown of wastes. Propane also can serve as a reliable backup energy source for the types of biodigesters that run off of their own energy production.

According to Konwinski, propane is also critical to the reliable operation of the engine generator in the biodigester.

"We have installed a propane system, making propane the sole fuel source for starting up and shutting down the system," he explained. "Propane's portability and ease of use in remote locations make it a great fuel source for use in biodigesters, especially in the agriculture sector."

"The agriculture industry has a growing need for renewable energy and new opportunities to take part in creating it," Leitman said. "PERC is confident that new energy sources such as biogas could help farmers and the country by boosting our economy and reducing our dependence on foreign oil. Propane has the opportunity to support this new technology because it is available across the country, it supplies efficient and reliable heat, and it is environmentally friendly."

PERC's vision in agriculture is that by 2010, the agricultural industry will recognize propane as a preferred energy source offering exceptional value. This value is achieved through a unique combination of product benefits, including cost-effectiveness, efficiency and productivity, reliability, portability, and environmental friendliness.

The Propane Education & Research Council promotes the safe, efficient use of odorized propane gas as a preferred energy source through investments in research, safety, and consumer initiatives. The Council was authorized by the U.S. Congress with the passage of the Propane Education and Research Act, Oct. 11, 1996.

SOURCE: PERC news release.