(Host) A Brattleboro group is looking into building a wood chip plant that would heat most of the buildings in the town’s business district – and generate electricity.
A consultant has offered some suggestions, but the group says more study is needed before a project is built.
VPR’s Susan Keese reports.
(Keese) The group believes it’s more efficient to heat many buildings by circulating steam from one large boiler than for every building to heat with its own furnace.
A so-called district heating system would be costly to install. The infrastructure includes a network of insulated underground pipes to circulate steam from one building to the next.
But advocates say it’s possible to generate revenue and avoid waste by using the steam to generate electricity as well as heat.
Michael Bosworth is co-chair of the nonprofit Brattleboro Thermal Utility, the group of local citizens that’s investigating the technology.
(Bosworth) "Part of our vision was that the fuel we would use would be biomass from the local forest because that’s a resource around here, instead of using oil that gets transported from elsewhere in the country or even more likely across the ocean."
(Keese) Vermont already has plants, like Burlington’s McNeil Generating Station, that use wood chips to produce electric power.
Around the state, 42 schools have cut their costs significantly by using wood chip boilers for heat.
Only a few places, like Middlebury College, are using the technology for both heat and power. Advocates say this sort of co-generation is used extensively in Northern Europe.
The Brattleboro group had a grant from the Public Service Department’s Clean Energy Development Fund to study the feasibility of such a system for the town. They also had funding from the town.
They hired Waldron Engineering of Exeter, New Hampshire, to study two options. But the results were disappointing for both.
Bosworth says that’s because the costs were too high and the returns to slow to attract investors.
(Bosworth) "So Waldron went back and came up with a hybrid model that would actually depend a little bit on oil. So, instead of 100 percent of thisbeing biomass, 90 percent would be. So we’d end up with some back-up oil-fired generators, particularly to meet the need in January andFebruary when you have your coldest days of the year."
(Keese) Board member Alex Wilson says that’s because a high tech wood boiler is more expensive to build than an oil burner.
Wilson says a wood boiler big enough to meet the so-called peak needs of the coldest days would end up with unused capacity much of the time.
(Wilson) "So by designing the system to supply 90 percent of the load with wood and leaving ten percent that could be supplied with oil, there’s actually a pretty big savings in the cost of the plant."
(Keese) The recommended hybrid plant would generate 2 megawatts or a little over six million dollars worth of electric power annually.
It would heat an area about the size of Brattleboro’s downtown.
The group plans to continue investigating the technology. Brattleboro is one of five Vermont municipalities, including Montpelier, Randolph and Burlington, that are looking into woodchip fired heat and power systems.
For VPR News, I’m Susan Keese.