East Bay Municipal Utility District (EBMUD; Oakland, Calif.) is making history. The district, which had been working to achieve net-zero energy consumption, has raised the bar. In addition to its program of collecting such organic wastes as restaurant grease, cheese waste, poultry blood, and winery wastewater from the surrounding area and using it to produce clean energy, it unveiled on April 3 a turbine that nearly doubles its capacity to produce energy, according to an EBMUD news release.
The 4.6-MW turbine increases the district’s energy production; making EBMUD’s wastewater treatment plant the first in the North America to be a net-energy producer. The district now can sell excess electricity produced back to the grid, the news release says.
During the past decade, the district began collecting fats, oils, and grease from throughout Central and Northern California for its food and organic waste program. These wastes were held in tanks, where they were transformed to nutrient-rich biosolids and methane gas. The program was so successful that it produced excess gas that had to be flared because the district had no way of converting all of it into energy, the news release says.
The new turbine supplements three existing engines to run the renewable energy system. The system now produces an average of nearly 7 MW of renewable energy with a peak capacity of approximately 11 MW, which would meet electricity demands of more than 13,000 homes, the news release says.
Water Environment Federation (Alexandria, Va.) President Matt Bond spoke at the unveiling event, calling this energy-generating plant expansion as a model for the industry. “EBMUD’s achievement has implications on a national and global level,” he said. “The wastewater treatment industry worldwide is in the midst of a major paradigm shift; instead of thinking of what we do as waste disposal, we are beginning to understand that wastewater treatment plants can be recyclers and, in fact, generators of valuable commodities like renewable energy, recycled water, compost, nutrient fertilizers, and even biodiesel.”
EBMUD Board President John A. Coleman said he hopes the district will provide an example that other wastewater treatment plants across the country can follow to benefit both the environment and ratepayers, according to the news release.