Koda Energy is an environmentally friendly energy project which is a joint venture with the 162-year old company, Rahr Malting of Shakopee. Considerably cleaner than a coal plant and considered CO2 neutral, this combined heat and power plant is the only facility in the United States which burns exclusively natural, non-manmade materials. Using a suspension boiler for maximum efficiency to burn only renewable products, its heat conversion rate is approximately 87% compared to coal, which is about 63%. Products burned in Koda Energy are agricultural and plant seed byproducts, materials which do not deter land from use as row crops. This biomass energy generation project is able to provide energy for Koda Energy and Rahr Malting, with excess sold to Xcel Energy.
Electric power generated averages 12.5 megawatts, with net power generated at approximately 24.1 megawatts. Amounts fluctuate based on largely on Rahr’s demand for heat. Rahr Malting uses the waste heat from the generation of electricity in their malting process.
Construction on Koda Energy began shortly after the September 13, 2007, groundbreaking. The facility began generating electricity in March 2009 and became fully operational in late May 2009.
The burning of byproducts from malting and food processing along with raw materials like wood chips, biosolids, and dry grasses is used to generate electricity and thermal energy at Koda Energy. The specific fuel mix burned in Koda is a blend of materials to maintain a consistent heat output and limit emissions.
General Mills provides about nine, 20-ton truckloads a day of oat hulls from the processing of cereals like Cheerios from their Fridley and St. Paul plants. Wood Chip of Princeton, an affiliate of Sylva Corporation, provides about eight, 20-ton loads a day, six days a week, of wood chips.
Rahr Malting blows about 95 tons of barley dust and other byproducts including malt sprouts and over and under sized seeds per day from the malting process to the fuel storage site.
Other products burned, deemed “Opportunistic Fuels” include ground up pallets, sawdust, sunflower hulls, and other agricultural seed products.
From the fuel storage site, fuel is moved using a drag conveyor to four hammer mills that reduce the particle size to a fine dust, approximately the size of talcum power. The dust-sized fuel particles are then blown into the boiler where they instantly ignite to optimize heat production while limiting emissions in a process designed to capture heat that otherwise would be wasted. Heat from the boiler generates steam that powers a Siemens steam turbine to generate electricity. A glycol loop carries the captured heat to Rahr Malting to meet their needs.
There is very little remaining solid waste in the form of non-toxic ash to fill landfills or use in agricultural processes or products. The biomass to energy process produces about 40,000 pounds of dry ash per day which is useful as a soil amendment for cropland, for composting. The ash could potentially be used in concrete for road projects. Air emissions are low and closely monitored at all times.
The SMSC is exploring options for burning native prairie plants in the Koda Energy facility. Koda Energy has the potential to be an important regional source driving a conversion of marginal cropland to perennial grassland cover/energy crop. This could reduce agricultural run-off, create wildlife habitat, and be an important biofuel source. The SMSC is currently conducting agronomical research on energy crops. (See Prairie Restoration) This research is the first of its kind at a functional scale to determine optimal plant mixtures and actual output of native prairie plants (tons/acre).
The Shakopee Mdewakanton Sioux Community sees Koda and the associated energy crop research as a very important tool for future self-sufficiency and sustainability. The SMSC is at the forefront of this technology in hopes that this work will benefit other tribes in years to come, especially those with a large land base. Producing energy from crops will create jobs, fuel self-sufficiency, and support sovereignty.
Biomass fuels are one of the largest sources of renewable energy. Purpose grown energy crops can sequester carbon in their root system thus lowering overall atmospheric carbon. There is no net gain of carbon dioxide (the major greenhouse gas) to the environment. Unlike coal burning generators, no mercury is released into the environment. The $60+ million construction project has created 15 new jobs with an annual payroll of $750,000 per year. Each year $6 million will be spent in the local area for biomass purchases. Another benefit is reduced soil erosion and carbon sequestration by dedicated energy crops.
Electric power generated averages 12.5 megawatts, with net power generated at approximately 24.1 megawatts. Amounts fluctuate based on largely on Rahr’s demand for heat. Rahr Malting uses the waste heat from the generation of electricity in their malting process. The balance is used for powering Koda and Rahr Malting with excess sold to Xcel Energy.