Wood chip boiler ready to heat HHS, Region 2

State-of-the-art heating system made possible by federal funds
By Joseph Cyr
Staff Writer
    HOULTON — It has taken nearly a year to see to fruition, but SAD 29’s new wood chip heating system has finally been installed and is ready to begin pumping out heat to Houlton High School and the adjacent Region 2 building.
    Paul Prosser, maintenance supervisor for the district, said the new heating system will be online Thursday, Feb. 24. A trial run will take place on Tuesday, Feb. 22, followed by another testing on Wednesday, Feb. 23.
    The school’s existing oil-based furnace will not be replaced, as it will be used in the spring and fall when only a small amount of heat is needed in the early morning hours, Prosser said.
Houlton Pioneer Times Photo/Joseph Cyr
CHECKING IT OUT — Paul Prosser, maintenance supervisor for SAD 29,  inspects the district’s new wood chip boiler Friday. The revolutionary heating system will be fired up for the first time on Tuesday, Feb. 22, with the official changeover from oil heat takes place Thursday, Feb. 24. The boiler was made possible through a federal stimulus fund grant.
    Last March, Houlton was selected as one of six schools and universities to receive federal stimulus funds through the American Reinvestment and Recovery Act of 2009, which is managed by the Maine Forest Service under the Maine Department of Conservation for the purpose of installing a wood chip boiler.
    The Maine Forest Service created the Wood-to-Energy Public Building Program to distribute those funds. The short-term goal for the program is to create and retain jobs in Maine; to achieve energy savings through wood-to-energy installations; reduce Maine’s dependence on non-renewable energy sources; reduce greenhouse gas emissions; and support sustainable forestry.
    Houlton High School received a grant in the amount of $750,000 to install the wood chip boiler to heat the junior/senior high school, as well as the adjacent Southern Aroostook Vocational Education (SAVE) Technical Center.
    The total cost of the project was just under $2 million. Interim-Superintendent Ray Freve informed the school board Monday evening that the biomass project would not be paid in full until 2022. By making the switch, the district could eliminate the need for about 65,000 gallons of heating oil each year.
    Converting to wood-based burners is something several schools are undertaking. Leavitt Area High School in Turner and Mt. Abram High School in Strong have already installed wood-based heating systems, and Caribou High School is in the process of building a system similar to the one installed in SAD 29
    Prosser added that 90 percent of the project has been done with local contractors. Swallow’s Electric performed all the electrical work, while McPartland’s Plumbing and Heating did the pipe work, while Building’s Etc. constructed the storage area.
    “We had to run all new piping, inside the ceiling, from this new room to our boiler room,” he explained. “We also had to run piping underground to the S.A.V.E building. Everything is ready to go. This unit will be our heating source.
    “And the wood chips we are going to burn will be purchased locally as well,” he added. “The only thing that isn’t local is the boiler itself. That came from Austria.”
    The district built an addition to the back of the school to house the boiler. A separate room was created to store the wood chips, which will be fed automatically to an auger via a massive moving hydraulic floor system. About 30 tons of wood chips will be dropped with each delivery. The storage building was designed to hold 120 tons of chips.
Houlton Pioneer Times Photo/Joseph Cyr
WILL IT FIT? — Construction workers guide the new wood chip boiler into its custom storage building on Monday, Jan. 17. For the past month, construction workers have been busy getting the school outfitted to make the change from burning oil to wood chips.
    Exactly how many tons of chips will be needed for a heating season remains unknown.
    “It’s anticipated that we will use about 640 tons per year,” Prosser said. “We won’t know for sure until we get up and running. It will depend on the type of wood.”
    Should the new unit fail for any reason, the oil furnace will kick in to provide heat for the two buildings.
    “These aren’t pellets,” he said. “We’re using wood chips that are roughly seven-eighths-by-seven-eighths in dimension. Our biggest concern is the moisture content found in the chips. We must maintain at least a 40 percent moisture content in our chips to start the boiler. That makes sure our emissions are where they need to be.”
    Because the auger is located in an open area on the floor, safety precautions have been put into place. Should the door to the auger room be opened, power to the grinder will automatically be shut off, Prosser said.
    Finding a supplier for wood chips was not difficult, Prosser said. The district will purchase its wood chips from Tom Gardiner’s mill on the B-Road in Houlton.
    “Tom was more than willing to help us,” he said. “He’s a taxpayer here in Houlton and recognized we used everything local.
    Emissions are not anticipated to be an issue either.
    “The emissions run through what is called a gasification process,” Prosser said. “What that means is it burns the smoke up. There will be very little emissions. There won’t be any ash, you won’t even see smoke. What you will see is steam coming out.”
    The new heating system will require a steep learning curve for the staff at the high school.
    “We will have to monitor this boiler constantly,” Prosser said. “We have men that work here that will have to have training and learn how to run this. We have others who do a ‘boiler-watch’ on the weekend, so they will have to know what to watch for.”