Renewable Energy Sources

As Great River Energy continues to grow, our new generation will include more environmentally sound renewable energy sources. Our generation sources already include wind energy, refuse-derived fuel and hydropower. Great River Energy is looking at ways to further diversify its energy portfolio by exploring biomass, fuel cells and other technologies as they become available.

Biomass – Refuse Derived Fuel (RDF)

Waste-to-energy plants, such as Elk River Station convert “refuse derived fuel” from mixed municipal waste into energy. Elk River Station uses refuse-derived fuel to generate up to 40 MW of electricity. These facilities are important because they reduce the amount of municipal waste going to land fills. Elk River Station burns between 250,000 tons and 300,000 tons of RDF annually. Since 1990, the plant has used more than 4 million tons of RDF. This means less municipal waste is sent to land fills and less methane is produced. Since methane has a global warming potential that is 21 times that of CO2, Great River Energy’s RDF consumption will continue to have a positive impact by reducing this greenhouse gas.

Using waste to generate electricity - after the implementation of area recycling and reduction programs - provides an efficient disposal method for garbage. The amount of waste entering the state's landfills is reduced by more than 400,000 tons each year through the operation of Elk River Station.

Biomass - Landfill Gas

As municipal waste decomposes in a landfill, methane gas is generated. Great River Energy purchases electricity generated from a landfill methane gas collection system in Elk River, Minnesota. Each year, we purchase approximately 20,000 megawatthours (MWh) from this renewable energy source.

Biomass - Anaerobic Digester

Great River Energy purchases the output from two anaerobic digesters located a dairy farms in Princeton, Minnesota, and St. Peter, Minnesota. The digesters capture methane from cattle manure and use it to run a 150-kW engine and generator unit.