Background

Since 1991, Foth has worked with the Winnebago County Solid Waste Management Board (WCSWMB) on their landfill gas to energy system which includes two landfill sites, a two-mile long pipeline/compressor sys-tem, two flare systems, and five engine-generators with a capacity exceeding 5 megawatts. In 2009, WCSWMB wanted to add an additional engine-generator to their combined heat and power (CHP) installation located at the Winnebago County Sheriff and Jail complex.

Approach

Foth provided engineering design and analysis, specifications, and construction administration for installation of a new landfill gas compressor/ conditioning system and the new CHP engine generator system. The new landfill gas compressor system design included integration with the existing blower/flare system and upgrades to continuously monitor gas flow and quality. The new CHP engine-generator system design included new heat exchangers and an absorption chiller. Foth also completed a systems analysis to address system efficiency issues.

Results

Foth assisted the County with selecting the most cost effective compressor system that functions with the existing blower/flare system and mini¬mizes operating costs.
Foth worked with the installation contractor to minimize the compressor/pipeline downtime by including contract incentives. This effort cut the system downtime from the scheduled 30-days to 15-days.
The Foth team collaborated with other consultants to integrate the heat recovery systems into the building systems including the absorption chiller systems. The design provided dump radiators that allowed the engines to continue operating when heat was not being used by the buildings.