MOULE: Trash to cash

By Jeremy Moule on March 26, 2009

It's worth paying attention to the county's Mill Seat Landfill.

Waste Management, which leases the landfill from the county and operates it, installed a landfill gas-to-electricity station a couple of years back. The company expanded it late last year by adding two more generators. There were six engines that had a generation capacity of 4.8 megawatts. With the additional generators, the station has the capacity to generate 6.4 megawatts. One megawatt can power about 1,000 homes.

The county gets a piece of the revenue generated by selling the electricity from the original project - $792,000 annually. Now, the County Legislature is considering a measure that would help finance the additional generators, that way the county can share in the additional revenues. The county should get an additional $238,000 annually, said Department of Environmental Services director Mike Garland during a Legislature committee meeting last night.

The plant operates on combustible gas generated by decomposing organic matter. The additional generators were added to the Mill Seat facility because, even with the existing generators, some of that gas was still being vented. Mill Seat's actually generating enough gas to support an additional three generators on top of the new ones, Garland said.

These types of facilities have a few benefits. For one, landfills generate copious amounts of methane, which is a potent greenhouse gas. Harnessing that gas and using it to generate electricity keeps the methane out of the atmosphere.

The flip side is that landfill gas-to-energy projects rely on landfilling, and may even encourage it.