Landfill gas powers U.S. ethanol plants, residential areas

By Susanne Retka Schill
The power of landfill gas is being demonstrated in three U.S. locations. Ethanol plants in Nebraska and Missouri are using landfill gas to replace natural gas, while a North Carolina project plans to generate electricity.

Mid-Missouri Energy Inc., a 40 MMgy ethanol plant in Malta Bend, Mo., plans to displace more than 90 percent of its natural gas usage with landfill gas supplied by Johnson County Landfill in Shawnee Mission, Kan. The deal signed in July requires the landfill to provide the ethanol plant with up to 3,300 million British thermal units per day of pipeline-quality biogas. The gas will be transported from the landfill through the Panhandle Eastern Pipeline to the ethanol plant 150 miles away. U.S. Energy Services Inc. developed the economic use impact analysis, negotiated the offtake agreement that was concluded in August and will provide thermal value management.

Mid-Missouri Energy will be able to capitalize on a provision in the Energy Policy Act of 2005 that allows any ethanol plant that replaces 90 percent of its direct fossil fuel use with a waste-derived fuel source to be eligible to receive an extra 1.5 renewable identification numbers (RINs) per gallon of ethanol produced. Mid-Missouri Energy can then sell these additional RINs.

Siouxland Ethanol LLC, a 50 MMgy ethanol plant in Jackson, Neb., has used landfill gas piped in from the L.P. Gill landfill a mile away since December, and U.S. Energy Services was assisting the landfill in selling six months worth of carbon credits at press time. "Without the sale of methane and carbon credits, a collection system was simply too expensive for a medium-scale operation such as ours," said Leonard Gill, owner and operator of the landfill. U.S. Energy Services is monitoring the plant's landfill gas usage and dispatching just enough of the higher-priced pipeline gas volumes required to meet pipeline balancing rules and avoid penalties. The energy company also coordinated the qualification of the project as a "carbon offset provider."

In North Carolina, Duke Energy Carolinas announced in August that it had reached an agreement with Methane Power Inc. to purchase two megawatts of electricity generated from the methane released at the landfill in Durham, N.C., which closed in the mid-1990s. Currently, landfill gas at the Durham site is being burned off. Under the agreement, Methane Power will install internal combustion engines and generators to burn the gas, produce power and deliver it to the Duke Energy Carolinas system. The project is slated to begin producing power by May 1 and will generate enough electricity to serve approximately 1,600 residential customers.