Tri-State has worked with its member co-ops to establish agreements with three hog-farming operations located in Wyoming and southeastern Colorado to sell their excess generation to the G&T. Waste from farms is first captured in a holding system, then released to a covered and sealed underground chamber known as an anaerobic digester. Inside the digestion pit, the waste reacts with a bacteria that is naturally found in the gut of the hogs. Anaerobic means that the process occurs in the absence of oxygen. As the bacteria digests the waste, it produces methane gas. The processed manure is no longer considered a hazardous waste byproduct of the operation and makes an excellent fertilizer that can be used on farmland.
When biomass is used to produce power, the carbon dioxide released at the power plant is recycled back into the regrowth of new biomass. This renewable and recycling process makes it possible to generate power without adding to air emissions. Biomass can be grown as bioenergy crops or gathered from forests, mills and landfills as a byproduct.
Hog methane biomass project
Member System serving load - Southeast Colorado Power Association, La Junta, Colo.
Member consumer - Colorado Pork, Lamar, Colo.
Type/size of generation - Three units: an 80-kilowatt piston engine generator set, a 30-kilowatt microturbine and a 55-kilowatt Stirling engine