By Shawn Perich
Last weekend, I smugly retired a ragged pair of Carhartt pants to the trash can. The pants were grimy with sawdust and bar oil, because I’d worn them all winter while cutting firewood. Now I no longer need them, because the task of putting up next year’s wood supply is now complete.
Like many rural Minnesotans, I choose to heat my home with wood, which is readily available from the local forest. A truckload of cordwood is relatively cheap compared with the cost of propane or fuel oil, but you must consider the time and effort required to cut, split and store it. I don’t burn wood so much to save money as to enjoy the exercise and satisfaction derived from putting up firewood. But in a very small way, I’m one the state’s energy producers.
While it may not rival the energy output of booming North Dakota, a significant portion of the Minnesota landscape is or could be devoted to energy production. In the south and west, wind farms tower over cornfields devoted to ethanol production. In the southeast, silica sand is being extracted for use in North Dakota oil fracking. In the north, millions of acres of public forests are increasingly scrutinized for wood biomass potential.
Land use associated with energy production isn’t necessarily beneficial to fish and wildlife, so the Minnesota DNR monitors what’s happening energy-wise across the state, the region, the nation and the globe. The man who keeps his finger on energy’s pulse is Mark Lindquist, DNR biofuels program manager in New Ulm. Last week we had a wide-ranging discussion about energy production across the state.
When I asked how energy production was affecting wildlife habitat, Lindquist referred me to a recent South Dakota State University study that found 1.3 million acres of grasslands and wetlands were lost between 2006 and 2011 in the Western Corn Belt, which includes Minnesota, the Dakotas, Iowa and Nebraska. The land conversion was driven by greater demand for corn and enabled by federal subsidies and crop insurance programs that allow farmers to plant marginal ground with little risk of financial failure.
Lindquist says about one third of the state’s corn crop runs through ethanol plants. He specifically says “runs through,” because about one third of the corn used in ethanol production becomes a high protein cattle feed called distiller’s grain. This is important, because historically, Minnesota corn is primarily used to feed livestock both here and abroad. China, for instance, imports corn to feed pigs. The worldwide demand for corn is growing due to increased consumption of meat and dairy products in developing countries.
Ethanol production has stalled out in recent years, because even though the EPA approved a 15% mixture of alcohol in gasoline for cars newer than 2001, no one seems to be jumping on the E15 bandwagon by building the infrastructure necessary to make it widely available. Lindquist says the alcohol product to watch is butanol, which is about 30% more energy dense than ethanol and is easier to mix with gasoline. A higher percentage of butanol can be added to a fuel mixture–the end result being producers can get 50% more corn into a gallon of gasoline.
Prior to the recent recession, there was a lot of buzz around the development of cellulosic alcohol, which could be made from crop residue, switch grass or even wood. Elsewhere in the country, new investments are being made in commercial-scale production of cellulosic alcohol, including Iowa plants that will use corn bran, cobs and stover. However, even though these new plants may annually produce millions of barrels of fuel, they will be just a drop in the nation’s energy bucket. We presently use 18 million barrels of fuel per day.
An area where there may be room for growth is in the production of biomass energy from wood.
“The challenge for biomass in Minnesota is we don’t know if we want to make electricity, manufacture chemical biofuels, make wood pellets to heat homes or build heating plants for small communities,” Lindquist said.
Large-scale industrial biomass projects are unlikely, because the new supply of cheap natural gas from fracking has changed the energy market and made it very difficult for biomass to compete. While there has been talk of new mills to make wood pellets for fuel, Lindquist said there are currently three pellet mills in Wisconsin, but none are operating at full capacity due to low demand. An initiative to wean power plants off coal in Ontario has led to innovations of burning a combination of wood and natural gas for industrial-scale production. Currently, the most opportunity for wood biomass in Minnesota seems to be in small community projects (discussions are underway in Ely and Grand Marais) and for heating turkey barns. The viability of these projects may hinge on future propane prices, because fracking is bringing more propane to the market place.
Using wood as fuel on a large scale has drawbacks and challenges, not the least of which is basic biology. Forests are less productive than farmland. While Minnesota could produce 100-200 million gallons of wood-based cellulosic alcohol annually, the state’s farmland presently could produce a billion gallons of corn ethanol. Another obstacle is deciding what wood is suitable for energy production, because wood is traditionally used for value-added products such as pulp and lumber. Under the federal Renewable Fuel Standard 2, the only trees allowed to be used for fuel are those grown in plantations. For naturally grown trees, only waste wood, slash (tree tops and branches) or brush and saplings are allowed.
Some of the reluctance to using pulp wood or saw logs for biomass has diminished as traditional forest products mills in Minnesota closed, Lindquist said. Even though demand for fiber has been reduced, timber harvesting remains the primary tool for managing healthy forests. Biomass production could help sustain northern Minnesota’s logging industry and the forest-based economy.
Before the recession, many in Minnesota were optimistic that we were on the brink of a new era, where locally produced energy would compete with and slowly replace fossil fuels. While the state has made some progress in that direction, new oil and gas supplies, particularly of natural gas, have become a dependable and affordable source of energy. With the exception of federally mandated ethanol, Minnesota’s hoped-for transition to bio-based energy is making very slow progress.
