Voices

Neither film nor its review tell the full story of biomass

BRATTLEBORO — Lisa Merton and Alan Dater's new documentary, Burned, is excellent in many ways, though weak in a few. Arlene Distler's review of the film captures a lot accurately but is also flawed on a couple of main points.

Their task has not been an easy one. The film covers a lot of ground: southeastern U.S. clear-cut logging that fuels huge electricity-producing plants in Europe; Berlin, N.H., answering its economic woes by hosting New England's biggest biomass power plant; the community of L'Anse, Mich.'s fight for its very health against a poorly regulated polluter in its midst -- all that, plus some of the principles of forest health and ecology.

Whereas the filmmakers, however, were careful to state (including in their advertising) that this was about the use of biomass to produce electricity and careful to differentiate that from the use of biomass to produce heat, that distinction was unclear in the review.

While both types of energy-producing plants give off carbon dioxide, which takes a number of years to be reabsorbed even if the contributing forests are managed sustainably, there are important differences.

Technology that uses biomass to produce electricity often operates at around 25-percent efficiency, while a plant that produces heat can operate at 75-percent efficiency. Thus, a lot more of the carbon stored in the biomass is utilized.

Also, biomass to produce heat is generally deployed on a smaller scale, often to serve individual buildings, and so not nearly equivalent to large biomass electric plants serving the grid. Both the needed inputs (of the biomass fuel) and the outputs produced (such as carbon) are less.

Serving the big plants in Europe certainly has required industrial-scale logging and processing in the southeastern United States. Merton and Dater's video footage is good evidence that this process is not utilizing sustainable forestry practices.

It is my layperson's understanding, however, that in our region we generally have much better harvesting and regeneration practices. This is partly because the states here take steps to encourage such approaches and partially because there is much more fragmented land ownership here, and many owners of the smaller holdings care deeply about their stands.

(Lest we in the Northeast feel too smug compared to the Southeast, however, we need only look back a little more than 100 years ago when economic drivers in our region denuded the Green and White Mountains.)

I also think the film's articulation of - and Distler's explanation of - “faulty [carbon] accounting” was not helpful enough.

I agree that the whole dynamic in the way the European Union incentivized biomass for electricity operations without ensuring good carbon accounting and good forest regeneration is a travesty, setting back the fight against climate change.

I do not, however, think its faulty accounting is equivalent to the basic principle that, over time, tree regrowth and soil regeneration in a sustainably managed forest landscape will largely offset the effect of the carbon released when the harvested trees are burned. (Thus, doing so is better than using fossil fuels that will not recapture the released carbon.)

Carbon accounting and sustainable forestry are complex stuff, but some very helpful sources explain them well. One example is the six-page 2016 “Summary of Carbon Emission Impacts of Modern Wood Heating in Northeastern US” from the Biomass Energy Resource Center in Burlington. Or, read many articles in the wonderful, nonprofit Northern Woodlands quarterly.

Burned does do an excellent job of listening to the healthy soil principles of people like Tom Wessels and displaying them in a combined above-ground/below-ground, flowing graphic.

This shows the complex systems at work as carbon, oxygen, and other molecules travel to, from, and within trees, and to their soils and interdependent neighbors within those soils. This is more evidence that if your harvesting practices leave a wasteland behind, there will be no easy way for the forest to regenerate.

What Burned does not do well is explore how widely good or bad management practices are being used in northern New England and upstate New York.

Thanks again to the Merton-Dater team who documented so much of the biomass-to-energy issue so well. Thanks also to Arlene Distler for getting a lot of it right in her descriptive review. I just hope that people realize neither the film nor the article are the full story.

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