Owatonna, MN — It takes energy to make energy. The electricity and fossil fuels needed to convert corn to ethanol can cost millions, depending on a plant’s size.
That’s why some Minnesota ethanol plants are using innovative technologies such as burning wood biomass or a syrup coproduct to lower energy costs.
Wood waste fuel
Central Minnesota Ethanol Cooperative in Little Falls, Minn. broke ground this fall on an $8 million on-site biomass plant. A gasifier will convert wood waste and other biomass to electricity. When the facility begins operating later this year, it will be the first of its kind in the country.
CMEC General Manager Kerry Nixon says the gasifier should reduce emissions, lower production costs and protect CMEC shareholders’ investment.
“We’ve created a market for an otherwise wasted product,” Nixon says. “It’s also creating jobs and that’s what it’s all about.” Wood waste is the primary fuel source, but Nixon says
dried distiller’s grains left over from making ethanol are a secondary source.
CMEC has received a $2 million USDA grant and another $2 million from Xcel Energy to help construct the gasifier.
Corn Plus in Winnebago, Minn. is reaping the rewards of another innovation. It is the first ethanol plant in the country to use fluid-bed technology to burn syrup, an ethanol coproduct, for energy.
General Manager Keith Kor says the syrup is normally sprayed back onto distiller’s grains and sold as feed. But there is more value in burning the syrup as it significantly reduces
the plant’s natural gas consumption. Corn Plus produces 44-million gallons of ethanol per year.
“We’ve been at full production since September 1,” Kor says. “In the month of October, we were able to reduce our natural gas consumption by about 50 percent. We’re excited about
that, but we think we can reduce it even more.”
The fluid bed uses air and heated sand to generate steam. It also produces ash that Kor says has value as fertilizer.
“A lot of people are looking at using various technologies to generate heat or electricity,” says AURI’s Alan Doering. “Ethanol plants use a lot of energy, but by using their own coproducts, they can cut down on a lot of the outside fuels they need to buy. Saving money is as valuable as making money.”