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King County Executive
Dow Constantine

Sale of emissions credits from landfill gas will net an estimated $500,000 a year from pioneering King County effort


When King County began collecting revenue last year from the sale of methane gas created from decomposing garbage buried in a landfill, it was only the start.


When King County began collecting revenue last year from the sale of methane gas created from decomposing garbage buried in a landfill, it was only the start. Now it will sell the emissions credits associated with this renewable energy source to Puget Sound Energy (PSE), bringing King County an estimated $500,000 more per year.

"We have harnessed a valuable commodity from something that was once a discarded byproduct," said King County Executive Dow Constantine. "The contract with PSE is just one example of how we are delivering on the commitment we made in the 2010 Energy Plan to stimulate the development of green energy, reduce greenhouse gas emissions and save taxpayer and ratepayer dollars."

The Metropolitan King County Council today unanimously approved an ordinance authorizing the King County Solid Waste Division to enter into a contract to sell the emissions credits to PSE.

"King County is taking advantage of the emerging renewable energy market to turn landfill gasses into energy to power people's homes and revenue for the county," said Councilmember Larry Phillips, Chair of the Environment and Transportation Committee and sponsor of the ordinance. "As one of the first and largest projects of this kind in the nation, we are demonstrating that reducing greenhouse gas emissions through innovation pays off."

"This is an agreement that benefits all parties," said Council Vice Chair and sponsor, Jane Hague. "Not only does it allow King County to avoid producing more greenhouse gases, it also generates $1 million for the County annually. It's a win-win situation."

King County and PSE joined forces in 2009 with Bio-Energy Washington (BEW), a company that builds landfill gas-to-energy systems, to turn the public's garbage into natural gas. The project uses the methane gas generated from decomposing garbage buried at the County's Cedar Hills Regional Landfill in Maple Valley, about 20 miles southeast of Seattle. Methane produced by the landfill is collected, processed and piped to PSE's natural gas-fired power generating plants.

Kimberly Harris, PSE president said, "We're using the landfill gas to light up to 24,000 local homes. This waste-to-energy project is an example of how environmentally sustainable actions can benefit our customers and communities."

Proceeds from the sale of the gas itself - currently estimated at about $500,000 per year and with potential for more - help keep solid waste disposal rates low and help offset other solid-waste expenses. Together with the sale of the emissions credits, King County expects the landfill gas project will be bringing in an estimated $1 million annually.

The contract with PSE is structured so that the County shares in profits that PSE gets when selling the emissions credits associated with the gas. The County anticipates that the sale of the rights to the emissions credits should provide an estimated $500,000 annually. The initial term for the contract is for 11 years, with provisions to extend it another nine years.

Because the converted methane gas from the landfill replaces an equal amount of nonrenewable natural gas, the landfill gas-to-energy project results in an overall reduction of emissions, including greenhouse-gas emissions - equivalent to taking 22,000 average passenger cars off the road each year.

More information about King County's landfill gas-to-energy project is available at:

Learn more about King County's 2010 Energy Plan at:

King County Executive
Dow Constantine
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