Biomass power plant planned for Minneapolisby Stephanie Hemphill, Minnesota Public Radio
People in south Minneapolis will hear about an electric power plant proposed for their neighborhood Thursday night. It is unusual to build a power plant right in the middle of town. This one would be fueled by wood chips.
Minneapolis, Minn. — Michael Krause is excited about a 70-year-old two-story brick building with a tall smokestack. It is on a tiny plot of land between the Soldiers and Pioneers Cemetery and a roofing contractor, just west of Hiawatha Avenue.
"There's a tip floor, there's a boiler room, there's a stack -- all of the basic elements you'd think of with an energy facility. And I'm thinking, I wonder if we could put new modern energy equipment in here."
Krause started thinking that six years ago, when the city was trying to find a new use for this Depression-era incinerator. Back then, he was running the Green Institute, just across the street. The group did some research, and came up with the idea of burning biomass to produce electricity.
Biomass in the form of wood chips is considered carbon-neutral -- it doesn't contribute to global warming.
"Because the plants, as they grow, sequester as much carbon dioxide as is released during combustion. So, because that loop is relatively short, and it occurs within a 10 or 15 year period, that's said to be carbon-neutral."
The plant would not only produce electricity; it would also put to use hot water, a byproduct of cooling the turbine. The hot water would create steam heat for the Midtown Global Exchange and two hospitals in the neighborhood.
That's an efficient approach, especially if it uses waste wood as fuel, Krause says.
"There are a million trees just in the city of Minneapolis alone, and there's a fair amount of waste generated: natural growth, natural mortality, diseased trees, storm damage, trimming around buildings and power lines, that's generated every year. Most is being hauled out of city."
And Krause says that'll be more than enough to fuel the power plant.
Not everyone agrees with him. Over in downtown St. Paul, District Energy operates a combined heat and power plant a lot like the one planned for Midtown Minneapolis.
Mike Burns, vice president of operations at District Energy, says at times he's had trouble getting enough wood chips close by. He's had to import material from the northern part of the state.
It's easy to get the idea there's plenty of wood around, until you realize his power plant burns 200,000 to 300,000 tons of wood chips a year, Burns says.
"I think everyone would conclude that there aren't 10,000 to 15,000 tractor-trailer loads of harvested urban wood residues sitting around anywhere in the Twin Cities area. I can assure you that's not the case, because being as deep into the market as we are, we know that's not the case."
District Energy is starting to look at importing agricultural waste like corn stalks. But the farther you have to go for fuel, the less efficient and environmentally-friendly the project becomes.
Another criticism for the Minneapolis project is coming from the Michael Krause's former employer, the Green Institute, the group that did the original research. The institute is pushing for a more thorough environmental study.
Plans call for 25 truck loads of wood chips to be delivered each day. There is already a lot of truck traffic in the area. Presently, the site is used as a garbage transfer station, which would be eliminated if the power plant goes through. The area is zoned industrial, but there are houses within a couple of blocks of the plant.
The state is poised to issue a permit for the project. The permit says the plant could emit as much as 160 tons per year of smog-causing nitrogen oxides, and various other pollutants.
There would be some environmental impact from the plant, Michael Krause admits, but he says on balance it would be much cleaner than the coal that is currently supplying much of the electricity used in the metro area.
"The electrical power in this neighborhood is going to come from somewhere. When we look at how much we're saving by generating this electricity from biomass versus coal, 240 million pounds a year of greenhouse gas emissions that we're saving compared to if we were just generating the same amount of electricity from coal."
Krause says small, local power plants like his are the way of the future. Most of the time the energy it produces will stay in the neighborhood, providing electricity for about 18,000 homes.
Thurday's meeting is being run by the Minnesota Pollution Control Agency and will explain the permit. It starts at 6:00 p.m. at the Holy Trinity Lutheran Church on East 31st Street in Minneapolis.
- Morning Edition, 12/13/2007, 7:24 a.m.