A day after residents of the city of Montpelier voted by an overwhelming margin to approve a biomass heating district proposal for state and city buildings, another group of Vermonters met to discuss the implications of biomass energy policy at the Statehouse.
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The Biomass Energy Development Working Group and the Department of Public Service convened to hear comments from special interests and environmentalists pertaining to the complex issue of how to move forward with biomass energy in Vermont.
Biomass, or wood chips from waste wood, is used to heat schools and other government buildings in Vermont, as well as to generate electricity at the McNeil Generating Station in Burlington and another plant in Ryegate. The purpose of the working group meeting was to sort out differences of opinion regarding the relative efficiency of the two different uses of this renewable source of fuel.
One of the main topics of discussion was how to increase the efficiency of biomass energy production, particularly for electricity generation.
“The group’s ultimate goal is to make a recommendation of biomass energy to the legislature that was high in efficiency,” said Sen. Ginny Lyons, D-Chittenden, a member of the working group.
One way to achieve a higher efficiency rate is by combining heat and power generation. For instance, the McNeil Generating Station in Burlington generates 50 megawatts of electricity, nearly enough energy to power all of Burlington, but at full load the station’s efficiency rate is approximately 25 percent. McNeil only produces electricity, and the leftover heat and energy the plant generates can be seen billowing away in smoke above the station. Ideally, a biomass power plant would use leftover thermal heat and create electricity with it, increasing the efficiency rate of the plant.
Tim Maker from Community Biomass Systems said there are many different ways of combining heat and power, but he said the most sensible thing to do is to run biomass systems for thermal purposes and then use any excess heat to generate electricity. Maker said he had never seen a study where the reverse — going from electricity to heat — had a better result.
Jeff Forward from Forward Thinking Consultants agreed with Maker and said that looking at thermal and then electricity “makes more sense.”
Beaver Wood Energy
Beaver Wood Energy has proposed the construction of two power plants in the southern part of the state, but the company met with stiff opposition from residents of Massachusetts for its proposed Pownal facility. The company still plans to build a plant in Fair Haven. Extra heat from the plant would be used to dry wood pellets for home and commercial use.
The Fair Haven biomass project would generate 29 megawatts of power. Thomas Emero, the managing director of development and operations at Beaver Wood Energy, told the working group the estimated efficiency rate of the plant would be roughly 35 percent.
“It’s very difficult to get higher than that,” Emero said.
The most efficient gas-powered plants, he said, only get up to 45 percent to 50 percent efficiency and coal is about the same.
Many of the working group participants questioned the merits of the Beaver Wood proposal. Forward said the pellet-making venture and the operation of nearby greenhouses were good in theory, but “even if you were to co-locate some sort of industry that wanted to use the heat in a remote part of the state … you don’t bump up those efficiencies because it’s really hard to get to 50 percent on a year-round basis.”
Working Group’s Reaction
Chris Recchia, the deputy secretary of the Agency of Natural Resources and a member of the working group found the comments “very useful.”
“They did convince me that it is a very complex issue, and there is no one answer,” Recchia said.
Recchia is interested in the information the three subcommittees, which are working on Modeling, Forest Health and Development issues, will bring to the group.
The working group, which meets monthly in the interim period between the sessions of the General Assembly, will give a presentation and report to the Legislature in January of next year, although according to Lyons an initial report will be issued in November. Members of the public will be encouraged to comment.
According to the interim report written in January of this year, the working group was established to “enhance the growth and development of Vermont’s biomass industry while also maintaining forest health.”