Morris, Minn. — Corn stalks will provide “fuel for thought” on a college campus in west central Minnesota.
The University of Minnesota, Morris plans to build a $6 million biomass gasification plant that will heat and cool the school’s two-dozen buildings. The gasifier will convert corn stover and other plant materials into renewable energy. And it will serve as a national model for rural schools, factories and communities interested in producing green power from local agricultural resources.
The biomass gasifier — the first in the state to run on crop residue — is part of UMM’s new Renewable Energy Research and Demonstration Center in Morris. Besides biomass power, the center will demonstrate wind energy systems, renewable hydrogen generation and storage, and methane power. The center’s goal, says Charles Muscoplat, dean of the U of M College of Agriculture, Food and Environmental Sciences, is to create opportunities for rural communities to develop their own local renewable-energy resources.
Making location an asset
UMM is a small public liberal-arts college set amid farm fields near the state’s western border. Here, fertile glacial soils produce abundant crops of corn and soybeans and support a robust livestock industry. But these bountiful farm fields are far removed from the world’s oil fields. “Our location is a disadvantage in terms of energy,” says Lowell Rasmussen, who directs UMM plant services and planning.
So, when natural gas prices soared in 2000, squeezing the college’s operating budget, school officials began asking, “How can we turn our location from an energy negative to an energy positive, an energy resource?” Rasmussen says. At the same time, he says, UMM’s 2,000 students began pushing hard for a “greener” campus. “That’s what started the discussions of a biomass gasification plant.”
Working with scientists at the university’s nearby West Central Research and Outreach Center (WCROC), UMM officials began looking at alternative energy sources. “We had a lot of expectations,” Rasmussen says. The fuel had to be clean, renewable and available on demand. It had to be price-competitive with natural gas. And it had to be locally-produced, to “keep our energy money in the rural area.” As it turned out, alternative fuels that fit the bill were growing just outside the college doors.
The Morris region produces more than 650,000 tons of potential gasification feedstocks a year, according to a 2003 survey by the Energy Environment Research Center in Grand Forks, N.D. The most plentiful: corn stover (the stalks and leaves left in the field after harvesting) and distiller’s grains, an ethanol byproduct.
An emerging industry
Gasification systems heat organic materials in a low-oxygen environment, producing a synthesis gas, or syngas, that can be substituted for natural gas. Large commercial gasification facilities, such as municipal garbage incinerators, have been used in this country for many decades. Wood- and forest-product gasification are also well established. But crop-residue gasification is a new technology that hasn’t yet been commercialized, says Michael Sparby, AURI project director.
AURI, a state leader in renewable energy development, helped UMM evaluate the feasibility of using this emerging technology to heat and cool the campus. In January, Coaltec Energy of Carterville, Ill., performed pilot test burns of 30 tons of corn stover and distiller’s grains in a commercial gasifier. Test results were encouraging, Rasmussen says. The corn feedstocks handled well and gasification efficiency was 99.6 percent, according to an April 2005 report from Recovered Energy Resources, the marketing arm of Coaltec Energy. Also, emissions with proper controls and ash quality were environmentally-acceptable, with high heat-recovery.
Rough-cost estimates suggest that corn stover gasification for heat can be price competitive, if natural gas prices rise above $5 per million Btu’s, according to Rasmussen. UMM’s 2005-2006 forward contract price for natural gas is twice that, he says. “As the price of natural gas goes up, we’re seeing even more incentive to continue exploring renewables.”
This spring, the Minnesota Legislature provided $6 million to build a biomass gasification plant at UMM. Rasmussen expects the Minnesota Pollution Control Agency (MPCA) permitting and licensing process to take at least a year. Crop residue gasification is so new, in fact, that MPCA has not yet developed permitting procedures, he says. Officials hope to have the new plant on line by winter 2007. The biomass plant will generate a new ag business, too, which will harvest and supply corn stover to the campus, Sparby says. He estimates that UMM will buy about $300,000 of corn stover and other feedstocks a year.
A sophisticated research tool
The gasification system will not only produce syngas to run UMM’s existing steam plant, it will be a sophisticated scientific tool, says Mike Reese, who directs WCROC renewable energy programs. “It’s unique, in that it will be both a working production facility and a research platform.”
WCROC scientists will use the biomass facility for a range of renewable-fuels research projects, Reese says. In the next five years, the research station will test gasification of perennial grasses, hybrid poplars and other potential crop feedstocks. University engineers will study biomass collection, transportation, storage and processing methods.
Scientists at the USDA-ARS soils research lab in Morris will work on related problems, such as using gasification ash for fertilizer, and how much corn stover should be removed from farm fields. “There will also be a strong economic research component,” Reese says. Longer-term research goals include processing syngas for transportation fuels and hydrogen.
A national model
The biomass plant will be an educational and outreach tool — a working prototype for others interested in adopting this technology, Reese says. Real-time operating data from the facility will be available via the Internet. And there may even be Web-cameras inside the gasifier, Reese says, “so you can see the syngas being produced.” In this way, what scientists in Morris learn about using agricultural biomass for energy “will be available to the world.”
Sparby expects UMM’s pilot plant to stimulate a lot of interest in making energy from farm products. This technology could bring new economic opportunities to rural areas, especially for farmers, he says. He foresees Minnesota farmers growing special biomass crops to supply locally-owned gasification plants — just as they do now for local ethanol plants.
“Farmers growing crops for energy, in addition to food and fiber — that’s the biggest economic promise of biomass technology.”