An extensive new heating project is underway at the Thompson School of Applied Science in Durham, NH which will provide biomass heat to Putnam Hall, Barton/Cole, the Veterinary Diagnostic Lab and the Macfarlane Greenhouses. The district heating project includes the construction of a new central boiler house with an interior wood chip silo and the installation of new underground piping to each of the buildings.
The boiler system features a new Viessmann Vitoflex 300-UF biomass boiler, two modern propane-fired boilers, and highly efficient circulation pumps to deliver the heat to all of the buildings in this small district. The biomass boiler will have an output of 2.45 million BTU/hour while the LP boilers will each have an output of over 3 million BTU/hour. A 1000-gallon buffer tank will be integrated into the biomass boiler system to increase efficiency and biomass heat availability.
The systems will be set up to burn screened semi-dry wood chips (25% moisture content) that will be blown into the 50-ton capacity masonry silo that is being built within the new boiler building.
Work started in early May on this project that is expected to be fully functional in September.
The project was conceived by the UNH Facilities Department as an alternative to replacing large sections of 30-year-old (failing) heat distribution pipes which tied the Thompson School area into UNH’s main central heating plant which is mainly fueled by “landfill gas”. This is the first large-scale biomass boiler system on the UNH campus.
By switching to this new small district, a substantial part of the load is removed from the central plant, allowing other areas to benefit from the now excess heating capacity. The new district also solves the problem of Barton/Cole being at the end of the old pipeline and on really cold days not getting enough hot water to warm the rooms.