Landfill Methane Greenhouse Gas Abatement with Peaking Power Production

Landfill gas (LFG), an approximately equal mixture of methane and carbon dioxide generated from landfilled waste, is estimated to comprise about 5% of total global anthropogenic greenhouse gas emissions. Its collection and use for power production is a growing but still underutilized renewable energy resource in the U.S. Two of the factors for this underutilization are: (1) poor collection efficiency; and (2) the fact that LFG has heretofore been used to fuel base power, whereas the greatest value for such distributed energy resources would be for peaking power. Therefore, this project will demonstrate the ability to operate landfill gas extraction and utilization systems on a diurnal basis for peaking power production. The landfill gas will be extracted at a variable rate, with three times as much extraction during the day, as compared to the night. The key issues are: determining how to carry out the variable extraction rate without increasing fugitive emissions of landfill gas or other pollutants; and assessing the low-cost, practical design modifications that will enable the production of peaking power. In Phase I, the system will be applied to a test landfill section containing over 60,000 tons of waste. A low cost design for peaking first will be operated conventionally and then as a bioreactor, in each case subjected to variable diurnal extraction. Gas output, gas composition, and landfill surface gas emissions will be monitored. Commercial Applications and Other Benefits as described by the awardee: Landfill gas recovery has the potential for generating (very roughly) 5,000 MWe of base power in the U.S. or, alternatively, up to roughly twice this power in peaking mode. Conversion of landfill gas systems from base to peaking power generation would greatly improve economics for the recovery of methane gas from landfills and increase the potential for greenhouse gas abatement.