Capturing Energy from Landfill Biogas

Klickitat PUD Commissioner Harold Hill at their Landfill Gas to Energy Plant.

Clallam County PUD signed an agreement to start receiving electrical energy generated from landfill biogas on August 1, 1999. The power purchase agreement is with Klickitat County PUD for output from their landfill gas fueled power plant in Roosevelt, Washington. The PUD’s purchase of 1 megawatt from the plant is approximately the amount of power consumed by 500 homes.

Klickitat County PUD in Goldendale, Washington is developing the region’s largest landfill gas-to-energy power plant. The plant is located at a 900 acre regional landfill, the fourth largest in the nation, in Klickitat County. Initially, the plant is generating 3.4 megawatts of electricity, using methane produced by 6 million tons of municipal waste at the landfill. Capacity is expected to grow to more than 23 megawatts within 15 years as the methane increases. The landfill accepts 2 million tons of waste a year, from as far away as Alaska and Northern California.

The plant is the ultimate in recycling – yesterday’s municipal waste will become tomorrow’s green energy.

Landfill gas-to-energy plants are recognized as renewable resources by the Northwest Power Planning Council and the Federal Environmental Protection Agency. In fact, EPA says, “This technology is the only renewable source of power that actually removes pollution from the air.”

That’s because methane, a natural byproduct of waste decomposition, is a potent greenhouse gas – 20 times more destructive than carbon dioxide. The gas is collected in a series of wells buried in the landfill. Hundreds of feet of collection pipe will transport the methane to equipment to compress the gas and filter out impurities. Clean, compressed gas is then delivered to gas engines, modified to run on methane, to produce electricity.