All Fired Up
By Ryan Newhouse
As more schools convert coal-fired boilers to burn biomass or build state-of-the-art energy facilities, they must creatively explore their “backyards” for sustainable fuel sources. If done correctly, this helps schools significantly reduce their baseline GHG emissions.
One school exploring all its options for becoming carbon-neutral is the University of Iowa (UI), and its biggest step towards that goal is an award-winning biomass facility that runs in part on a breakfast cereal byproduct.
“Our goal is to be on 100 percent renewable [energy],” says Ferman Milster, University of Iowa’s Assistant Director of Utilities. The campus began using one of its two boilers for biomass commercially in 2004, and since then it has been burning one very particular source of biomass-discarded oat hulls from a Quaker Oats facility in nearby Cedar Rapids. The oat hulls are co-fired with coal so that 50 percent of the heat output of that boiler comes from biomass.
“In 2009, we shipped in and burned 24,000 tons of oat hulls,” Milster explains. The oat hulls cost UI about half as much as coal, per 1 million Btu of energy produced, and they produce 7,000 Btu/lb. versus coal’s 11,000 Btu/lb.
Oat hulls are also very lightweight compared to coal-7 lb/ft³ versus coal’s 55 lb/ft³, and they get trucked in 20 miles from the plant to the campus biomass facility. “We get our coal from southern Illinois,” adds Milster. By not burning as much coal, UI estimates its actions are the equivalent to taking 1,200 passenger vehicles off the road each year, and the energy generated from the oat hulls alone is enough to power about 900 homes annually.
The Quaker Oats facility in Cedar Rapids produces close to 100,000 tons of discarded oat hulls annually, and the 75 percent that UI doesn’t use goes into livestock feed and bedding, or various high-fiber foods for human consumption. Burning the oat hull biomass at UI, however, produces a full 11 percent of the entire University’s energy use and saves the school over $750,000 annually on its utility bill. All this has been accomplished without the school having a technical precedent for burning light, fluffy oat hulls. In fact, UI had to make several modifications to its boiler before it worked properly.
The University of Iowa also uses a second boiler for backup and testing other types of biomass fuel sources. “I’m sitting here looking at eight or ten bags of stuff people have made,” explains Milster, “wood chips and wood pellets, and they are all asking me, ‘Can you burn this?'” Already the EPA has sponsored an extensive wood pellet test at UI, but the school found that the wood pellets (brought in from Minnesota or Wisconsin, according to Milster) would have cost them twice as much as what they pay for their coal.
“We’re not going to go out and do something that costs us a whole bunch more money,” says Milster, “and that’s key for this. It’s one thing to be environmentally-friendly, but it’s another thing to be environmentally-friendly at a cost you can afford.”
Green Mountain College (GMC) in Vermont is also examining the “costs” of biomass and responsible sourcing in the region. Not to be overshadowed by the biomass successes of its neighbor, Middlebury College, GMC will be testing its new $6.8 million biomass facility over the next two months, hopefully being fully online by April 2010.
“It’s going to help us reduce our carbon footprint by over 50 percent,” explains Dr. Williams Throop, Provost and Vice President of Academic Affairs at Green Mountain College. “It will heat almost all of our buildings and shift about 85 percent of what has been oil to biomass.” GMC also expects to save over $200,000 annually in utility costs and produce 20 percent of its electricity from biomass.
The biomass facility will burn roughly 4,400 tons of wood chips annually, “all of which will be sourced within a 50-mile radius,” says Dr. Throop. GMC will be contracting with the same biomass broker as Middlebury, Cousineau Forest Products, and first preference for materials is wood byproduct, not clear-cut and chipped-up trees.
Still, “it’s very hard to get good data on where this stuff is coming from,” explains Dr. Throop.According to the carbon accounting protocol of the Intergovernmental Panel on Climate Change(IPCC), use of biomass fuels for energy does not add to the net amount of carbon in the atmosphere because the same amount of carbon that is released during combustion of biomass fuels is absorbed from the atmosphere by the plants while they grow.
Additionally, the Voluntary Carbon Offset Protocol, published by the American College & University Presidents’ Climate Commitment (ACUPCC), says that “fuel switching can produce legitimate offsets by reducing the amount of emissions produced from the use of fuel for the same activity.”
According to Lucas Brown, professor of Environmental Studies at GMC, however, it does pay to look “upstream” in regards to one’s biomass source.
“Once you go beyond the point-of-use and start looking at upstream costs,” Brown explains, “it gets extremely complex really fast. With wood chips, for instance, while a tree grows it sequesters carbon. You cut it down, burn the chips, the carbon goes back into the atmosphere, feeds another tree. It should be a closed loop, but there is a certain amount of energy involved in the extraction, processing and distribution associated with those chips. But, at least according to the IPCC, if you transport those chips 30 miles versus 300 miles, it doesn’t really matter because it’s still a climate-neutral fuel source.”
GMC and Middlebury have been discussing in detail how much they would be willing to spend on sustainable sourcing for their biomass. “For example,” Brown says, “if we’re spending $35 a ton for wood, would we be willing to pay $70 a ton if it could be documented where it came from and that it was sustainably forested?”
It’s not as if Vermont is in danger of losing its forests in the near future, but these are the larger questions both GMC and Middlebury want to keep in mind. In fact, according to Bill McKibben’s book, Hope, Human and Wild, Vermont has grown from being only 35 percent forested in 1850 to being 80 percent forested today. McKibben writes, “Not only do we have our woods back to use more wisely as the economic base of a more sustainable economy, we also have our woods back to help in reshaping our desires.”
“Within a 60-mile radius [of GMC],” explains Brown, “170,000 green tons of trees grow annually, in net growth. It gives you an idea how small of an impact burning 4,400 tons has on the forest ecosystem. We are very confident there is a sufficient supply for us, and we’re doing our best to make sure it’s all harvested locally and harvested sustainably.”At the University of Minnesota-Morris (UMM), sourcing biomass for their facility has not been a major issue. There is plenty of nearby corn stover at its disposal. However, UMM has been delayed in getting its biomass facility up and running since launch was first slated in October 2008.
“Unfortunately, our facility is not working as planned,” says Joel Talleksen, researcher for the UMM biomass project. “There are some engineering issues. Some problems probably could have been predicted, but for others we didn’t have someone else’s experiences to know exactly how to do things, so we did them the best we could.”
The UMM biomass facility, when it is operational, is anticipated to provide 80 percent of the school’s heating and cooling needs, and in conjunction with other UMM alternative energy projects, Talleksen suggests UMM may even become carbon-negative, putting extra energy back on the local power grid.
“In the current economic climate, with energy prices having dropped hugely,” Talleksen explains, “it’s becoming a harder sell to do some of the things we wanted to do.” One phase of the biomass project that did get completed was the addition of absorption chillers, which will replace electric chillers UMM is using now to cool the campus in the summer months.
“Right now,” explains Talleksen, “in the middle of summer our campus is using more electricity than any other time of the year, and we have no students around.”
As for the actual biomass facility, not much has been burning except for various testing procedures, but Talleksen has not been deterred from realizing the facility’s potential: “[Biomass] is an emerging industry, and that’s one of the reasons a university is a good place to do some of the research on this, because we can have small hiccups and still go forward as planned.”