Biomass

Biomass is solar energy stored in organic matter. To use that energy as fuel for electricity generation, the organic matter is typically burned or converted into biogas and burned.

MGE has used both forms of biomass.

Landfill gas

In landfills, biomass rots and releases methane gas, also called biogas or landfill gas. Some landfills have a system that collects the methane gas so that it can be used as a fuel source. Collecting and using landfill and biogas reduces the amount of methane that is released into the air. Methane is one of the greenhouse gases associated with global climate change.

MGE purchases electricity from the Dane County Rodefeld Landfill where generators run on methane gas. Dane County taps into the methane gas produced naturally in the landfill. The generators export the energy to MGE's distribution system. On average, the Rodefeld generators produce about 25,000,000 kWh per year, or enough electricity to serve the needs of nearly 3,500 homes.

MGE funded a demonstration project to determine the potential for a Stirling engine to use waste methane from smaller landfills to power a generator to make electricity. This project is currently on hold.

Paper-derived fuel

MGE has burned various forms of biomass in our Blount Generating Station boilers since 1979. We partnered with the City of Madison to burn shredded municipal waste, mostly paper and plastics. When that supply ended, we tested and used other pre-consumer waste products. We also tested use of switchgrass. From 1993 through 2008, Blount burned pre-consumer waste as fuel.

For more information

Landfill Gas-to-Energy Fact Sheet [329 kB PDF]