University of Missouri sees biomass as future for campus energy generation

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1 University of Missouri sees biomass as future for campus energy generation University is developing initiatives to help develop biomass market in the state Progressive is one way to describe the University of Missouri, located in Columbia, Mo. The university was founded in 1839 and at the time was the first public university west of the Mississippi River. Over the years, the university has become a recognized leader in providing an unparalleled college education and as a world-class research center. Innovation and progressive thinking have been keys to the university in other areas as well. One of those areas is how the university produces electricity and steam for the campus facilities. The current cogeneration power plant is a 66 mw combined heat and power facility that has been in operation since The facility produces steam that is used twice; first to generate electricity, then the steam is piped though the campus to heat and cool buildings. While the power plant has traditionally been powered with coal and natural gas, the university began experimenting with alternative fuel sources back in the 1990s. We ve always been interested in alternate fuels, says Gregg Coffin, superintendent of the University of Missouri Power Plant. We began conducting different alternate fuel tests back in the 90s using wastepaper pellets and tire-derived fuel. The wastepaper pellets didn t work well from a cost standpoint, but we have consistently consumed an average of about 350,000 to 400,000 shredded passenger car tires a year over the past 16 years as a supplementary fuel. In 2005, Coffin approached a group of university researchers about using biomass as an alternative fuel source. The team read and heard a lot about institutions that had tapped into industrial sources of biomass. In fact, another University had successfully used oat hulls in their power plant and that motivated the University of Missouri to put together a campus group with a common interest in biomass to research the potential opportunities in using biomass.

2 Since then, the university has experimented with woody biomass sources, such as mill waste, tree trimmings, development clearing and chopped pallets. They ve also tested corn cobs and switch grass. Biomass is basically organic waste that can include scrap lumber, forest debris, agricultural harvest waste. These organic wastes would otherwise be dumped in landfills, openly burned, or left as fodder for forest fires. Biomass power uses these natural materials to generate clean, renewable electricity, while reducing greenhouse gas emissions. We are co-firing wood waste up to 5 percent with coal in our existing plant boilers, says Coffin. So far, wood chips have worked best, and I anticipate we will need to source between 5000 and 6000 tons of woody biomass this year. However, our tests with corn cobs have shown a lot of promise as well. Coffin hasn t experienced any difficulties with biomass on the combustion side. Most of the difficulties have been in material handling. Corn cobs are lighter than wood and carry a little more heating value, but it takes a lot of corn cobs to meet the needs of the boilers. On the other hand, woody biomass is easier to handle, but carries about half the heat value of coal. Our existing boilers can handle up to 10 percent biomass, a higher percentage would require modifications to the fuel system, says Coffin. While 5000 to 6000 tons may not seem significant, it has created challenges in an area that doesn t have an established market. So in essence, Coffin and his team are trailblazers, and to date, the response has been favorable. It has taken a lot of discussions and presentations with many people in the wood-waste processing and forest industry, says Coffin. That dialog still continues and will as long as we are expanding our use of biomass as a fuel. When we started there were a few people interested. Now I get calls from suppliers all the time. The university currently purchases its woody biomass from various sources with an annual fixed- price bid. The power plant will not pay more for biomass than what they pay for coal on an equivalent heat-value basis, limiting any increased operational costs to the university.

3 The price cap (on a per-ton basis) is established based on the equivalent heat basis for coal. A competitive bid process is used to identify and select one or multiple suppliers, and so far it s worked well. Once a contract is extended to the supplier, they are responsible for delivering a 3-inch minus product on a set delivery schedule. Due to space limitations, the university can only store a few days worth of biomass on-site. So communication is imperative with their suppliers to deliver product on time and within a set schedule. So far using biomass as an alternative fuel source has had a positive impact on the university campus. Overall greenhouse gas emissions have been reduced by 7000 tons per year and the reduction in carbon dioxide emissions is equivalent to planting 28,000 acres of trees. In addition, by sourcing locally grown biomass, the university has reduced diesel fuel consumption by almost 16,000 gallons per year that would have been used to transport coal to the power plant from neighboring Illinois. Moving to 100 percent biomass About this same time the university began exploring options to increase steam capacity. One of the five existing boilers was unreliable, and as the campus grew, the overall power plant lacked the capacity to keep up with past and anticipated growth. We needed to add steam capacity at the power plant, so we began looking at our options, says Coffin. We could expand using coal, but that would be problematic from an environmental standpoint. Obtaining a permit would be difficult, and we anticipated pushback from the campus and local community in regard to adding another coal-fired boiler. Coffin and his team also explored firing the boiler with natural gas, but eventually settled on biomass as the most viable expansion option. The university had been co-firing the existing boilers with biomass and realized it presented an opportunity. We felt we could install a biomass boiler much more cost-effectively for the lifecycle, compared to natural gas, says Coffin. Plus the biomass would give us several benefits that a natural gas boiler would not. Biomass is 100 percent renewable and would provide an investment back into the local economy instead of purchasing coal and natural gas from other states. Moving to biomass also provides an opportunity for campus researchers, many of whom have participated in the development of the university s biomass fuel project over the years. The

4 research community could expand their research and help develop the biomass infrastructure growing, harvesting and preparing of biomass in the state of Missouri. However, the decision to build a biomass boiler was mainly made on providing the most cost- effective, reliable feed supply for the campus. We didn t just decide to replace the boiler because it was the right environmental thing to do, says Coffin. It was really based on the need to replace the boiler and how best to replace that in the long term. The university is installing a 100 percent biomass-fired boiler that will produce 150,000 pounds of steam per hour. This will increase the power plant s steam output by 30,000 pounds per hour once the unit is replaced enough to build capacity and meet anticipated growth. The new boiler should be in operation in We have the potential with this new biomass boiler to displace about 25 percent of our coal consumption, says Coffin. It s a pretty significant jump considering we re currently at less than five percent. Creating a sustainable supply chain The biggest challenge according to Coffin will be sourcing biomass fuel for the boiler and having adequate storage and handling systems in place to serve the unit. The new boiler will require 100,000 tons of biomass annually, which is a substantial jump from the 6000 tons being sourced today. I ve spoken to a lot of people that have started biomass facilities and they all end up going in with not all the fuel sources identified. I think that s the case in our area, says Coffin. We can t expect to have an established biomass market until demand increases. Right now there are only a few biomass consumers in Missouri, and as demand increases the market will develop to meet that demand. There are a number of players interested in becoming biomass suppliers to the university and Coffin routinely fields calls from potential suppliers. Another challenge is storage, as the university does not have the landmass to store substantial quantities of the biomass on-site. Several months worth of biomass fuel will need to be stored off-site once suppliers have been identified. We foresee using a fuel broker to coordinate the procurement, specifications, storage and delivery of the biomass fuel, says Coffin. Right now our focus is on sourcing woody biomass,

5 but we can also use corn cobs as well and the agriculture industry is working on a number of collection systems. Coffin sees about a third of the woody biomass fuel coming from waste stream sources mills, chopped pallets, development clearing, tree trimming and ice storm damage a third from forestry management and thinning efforts and another third coming from growing biomass instead of traditional crops. We are tapping into the resources here at the university, says Coffin. The university forestry department has been actively involved with the project, helping source woody biomass from waste trees. They re highly interested in supporting a forestry thinning effort and establishing the criteria for that. According to Hank Stelzer, a state forestry extension specialist for the University of Missouri, the state forests are not in the best of health. Forest thinning would greatly improve the health and quality of our forests and at the same time provide a good, renewable source of fuel for the plant, says Stelzer. We re developing a set of thinning and harvesting guidelines to make sure we protect the long-term integrity of the state forests, yet create a sustainable source of biomass, not just for the university but for other facilities across the state. Biomass a new value-added crop The university is exploring options to grow woody biomass crops on marginal ground and in the river bottom areas across the state that were affected by the floods back in The land in these areas is no longer economically viable for traditional row crops as the soil profile features a deep sand formation. While this type of soil isn t suited for row crops, it is ideal for certain species of trees, such as willow and cottonwood. Stelzer and other forestry faculty are in the process of establishing research plots that will test various species of trees to determine their potential as an energy crop. The University of Missouri s Center for Agroforestry began experimenting with different species of cottonwood and hybrid poplar back in the late 1990s and over the years has identified select clonal varieties that are well-suited to the soil conditions in Missouri. Today, the research is being done in collaboration with the State University of New York, University of Minnesota and Mississippi State University.

6 Traditionally willow and cottonwood trees have been planted in a 10-foot-by-10-foot spacing pattern and were allowed to grow for five to six years before being harvested. However, Stelzer says that current thinking is to plant the trees in a double-row configuration, where two rows will be planted close together on 2-foot-by-2-foot centers with a five-foot space and then another double row of trees. Basically we will set the cuttings in year one and clip out the tops to help promote multiple sprouts, says Stelzer. The trees will grow for three years and reach a height of up to 20 feet with several stems (8 to 10) coming from that clump. The neat thing is, especially with willow and cottonwood trees, is the ability to harvest the trees about every three years or six times over the 20-year life of the tree. At 20 years of life the trees will be removed and the process starts all over. Stelzer says that producers can expect to produce 9 to 13 dry tons woody biomass per acre at the end of the three-year growing cycle and this number will go up as the university identifies higher yielding varieties over time. At the current price the power plant is paying ($35 / ton) that would generate $315-$473 in revenue to the farmer on just one acre. That s enough to get a farmer s attention considering the input and production costs are minimal. Harvesting the woody biomass is another issue, but a team of researchers at the State University of New York have been working with New Holland, a leading agricultural equipment manufacturer, to develop specialized equipment to harvest the woody biomass. Basically, the team has created a harvesting head that is fitted onto a New Holland forage harvesting machine. As the machine moves through a field of trees, the harvesting head clips off the trees, which are then fed into the machine and a cutter drum chops the woody biomass into small pieces, similar to processing a tree in a brush chipper. The resulting processed woody biomass is placed onto trucks and transferred to a storage site. The MU Forestry Department, in cooperation with the MU Center for Agroforestry, is developing a pilot program at the Horticultural and Agroforestry Research Center (HARC) in New Franklin, Mo., that will include test plantings of various tree species to produce woody biomass. The pilot will

7 also test harvesting options and deliver the resulting wood chips to the power plant. The purpose of the pilot project is to show farmers how they can adapt this new crop to their farm. Woody biomass production has the potential to be more profitable and economical than traditional row crops, especially in the Missouri river bottoms laid waste by the floods of 1993 and 1995, says Stelzer. It also allows farmers to regain lost production acres with fewer disturbances to the land compared to traditional agronomic production. We re also enabling the farmer to integrate forestry practices into other areas of the farm that will not only provide another source of income, but also serve as a sediment, nutrient and pesticide trap in the root systems of these trees. Considering more than woody biomass Coffin and his team are also seriously exploring how to utilize corn cobs in the new boiler as the University is located in the heart of Missouri corn production. Plus the new boiler technology burns at a lower combustion temperature making it more suitable to agricultural-based fuels. The new boiler can handle a full-size cob and the opportunities to source cobs as a fuel source are abundant in our state, says Coffin. The biggest challenge is collection and storage. However, companies are developing innovative collection systems that are showing promise. We just need to address how to deal with such a large volume of material. This project will truly be a test to see how the biomass industry can and will develop in the state. However, should the price of biomass become more expensive than natural gas, Coffin has the ability to switch the boiler over to gas until the price of biomass comes back in line with fossil fuels. Either way, the university and the Columbia community will see a reduction in conventional emissions. I believe the campus community appreciates this opportunity to produce energy from a renewable crop and reduce greenhouse gas and carbon emissions, says Coffin. We re creating something here that s a win-win for everyone involved and from the calls were receiving, there s a lot of support for the direction we re taking. # # #