OAKLAND, April 3, 2012
Waste to power program becomes blueprint for communities nationwide
The East Bay Municipal Utility District unveiled its newest green technology today. A state-of-the-art turbine nearly doubles the utility’s capacity to produce clean energy from waste previously thought to be too gross, too toxic and too difficult to manage. Now, communities across the nation are following EBMUD’s lead and developing similar programs to convert wastes into renewable energy.
“We’ve turned wastes into commodities. The same materials that once no one wanted to touch, now have become so valuable everyone wants them,” said EBMUD Director of Wastewater David Williams.
In the past, the wastewater treatment industry focused exclusively on treating and disposing of sewage. No wastewater utility wanted to treat organic wastes, like fats, oils and grease, food scraps, or dairy and animal farm wastes. Even though they could be detrimental to the environment, with nowhere to put them, these waste streams were left to decay in landfills or pollute groundwater.
Over the past decade, EBMUD’s nationally-recognized food and organic waste program turned that notion upside-down as it recognized the high energy value of those waste streams and welcomed them into its plant. The utility expanded its collection of septage waste and began accepting items as varied as restaurant grease, cheese waste, chicken blood and winery wastewater from throughout Central and Northern California. “Some thought we were crazy for bringing things like fat, oil and grease into the plant,” said Williams.
Into huge tanks the organic wastes went, and in a few short weeks they degraded and became nutrient-rich biosolids and methane gas. Sometimes, the plant would produce so much excess gas, EBMUD had to flare the methane because it had no way of converting all of it to energy.
With the addition of a 4.6 megawatt turbine, as big and powerful as a jet engine, EBMUD is the first water and wastewater utility in the nation to sell the excess electricity it produces solely from waste material back to the grid. Today, the new turbine supplements three existing engines; combined they can produce enough electricity to meet the demands of more than 13,000 homes.
One impetus for EBMUD’s new turbine and increased production capacity was the energy crisis that roiled California and the nation nearly a decade ago. “We had to find a way to control our energy costs,” said Williams. On most days, EBMUD produces more than enough electricity to power its wastewater treatment plant at the foot of the Bay Bridge in West Oakland.
“We’re proud to have pioneered this technology over the past decade,” said EBMUD Board President John A. Coleman. “Nearly every community across the nation has a wastewater treatment plant. Now they can follow our lead and turn the most unsavory wastes into clean energy for the betterment of the environment and ratepayers.”