Creating energy out of waste

The LOTT Alliance just grew a little more independent on the heat and energy front.

For years, the sewer partners burned methane gas generated at their wastewater treatment plant in Olympia through a flare that juts into the sky above the plant's boiler room roof.

That flare has been all but snuffed out by a $2.4 million project that converts the methane gas into heat and electricity.

It's enough heat to meet the needs of the treatment plant, the new LOTT Regional Services Center set to open this summer and the planned neighboring Hands On Children's Museum.

And the electricity from the cogeneration project should trim LOTT's annual $1.3 million power bill by about 10 percent, LOTT executive director Mike Strub said.

LOTT will pay for the project in about five years, thanks in large part to a Puget Sound Energy grant that covered 70 percent of the project cost, Strub said.

"What really triggered the project was the LOTT board wanting to reduce our carbon footprint," Strub said.

The board consists of elected officials from Lacey, Olympia, Tumwater and Thurston County.

"As a public wastewater-treatment facility, responsible use of community resources represents the core of our work," said Doug Mah, Olympia's mayor and the LOTT board president.

Flaring of the gas was wasteful and inefficient, LOTT officials said. About 14 percent of the methane, which is 21 times more damaging than carbon dioxide as a greenhouse gas, escaped into the atmosphere when the flare was used.

Historically, the plant has produced about 116,000 cubic feet of combustible gas daily, according to LOTT estimates.

The new system includes an engine that runs on the gas to generate electricity and heat-recovery units that transfer heat from the engine exhaust to an existing hot water loop serving the plant.

Electricity generated should be about 2 million kilowatt-hours a year, enough to power 165 homes. The reduced greenhouse-gas emissions -- the engine burns 99.9 percent of the methane -- is equal to eliminating greenhouse-gas emissions from 306 cars, according to LOTT calculations.

"What I like about this project is that it keeps employees thinking about how to conserve and efficiently use resources," said LOTT operations supervisor Ben McConkey. "And it goes a long ways toward improving employee morale."

The project should help LOTT and the museum in their quest for Leadership in Energy and Environmental Design (LEED) certifications from the U.S. Green Building Council. LOTT is seeking platinum, which is the highest green-building rating LEED offers.

Another energy-efficiency project at the Budd Inlet plant is slated for completion in August. Upgrading the treatment plant's aeration blower is expected to save enough power for 45 homes and save LOTT $48,000 on its annual electric bill. Puget Sound Energy is paying for 70 percent of the nearly $430,000 project.

John Dodge: 360-754-5444