Recap on the Massachusetts biomass rules: how we got here, what’s at stake

Climate science shows that to avoid catastrophic warming, we must reduce emissions and take CO2 that’s already in the atmosphere out – most likely by restoring and expanding forests.  We need to cut our net emissions in half in the next ten years, and reach emissions neutrality – with emissions balanced by uptake – by 2050. (See our summary of the latest climate science from the IPCC – including the call for a reduction in bioenergy generation! – here).

That’s why burning forest wood for energy is so counterproductive. Wood is technically renewable, but wood-burning power plants emit more CO2 per unit energy than fossil-fired plants, pumping greenhouse gases into the atmosphere just when we need most to reduce emissions. Forests cut for fuel may grow back eventually to offset those emissions, but this takes decades to more than a century. The result is a net increase in CO2 emissions to the atmosphere just when it’s most important to reduce emissions.

This was the big finding of the Manomet Report that was commissioned by Massachusetts to inform the state’s biomass energy policy. The study concluded that net emissions from wood-burning power plants that burn a mixture of trees and forestry residues exceed emissions from a same-sized coal or gas plant for years to decades (even under a best-case scenario that assumes forests grow back perfectly). The study was published in a peer-reviewed journal – you can download it here.

See Table 2 for the outcomes of Manomet; see further below for an explanation of why it matters if fuel is sourced from whole trees or residues.

Manomet outcomes

Table 2. The main conclusions of the Manomet Study: Even assuming efficiency of 80% or more for thermal-only units, it takes 15 – 30 years for net CO2 from biomass units to be drawn down to the same level of an oil burner, and 60 – 90 years for gas.  For electricity-only plants, where efficiency is around 24%, it takes much longer for net emissions to fall to the same level as net emissions from a fossil-fired plant.

The Manomet Study was commissioned by the state because back in 2008 or so, there were three big wood-burning power plants proposed Massachusetts (in Russel, Greenfield, and Springfield. The Springfield plant, confusingly named “Palmer Renewable Energy,” may still be built – see below). Scientists and activists came together to defeat these proposals, in part by launching the “Stop Spewing Carbon” campaign, a petition drive for a ballot measure that would have taken most polluting energy sources out of the state’s Renewable Portfolio Standard (RPS).  The petition drive collected over 100,000 signatures and qualified for the ballot. In the meantime, however, DOER had realized there was a problem with CO2 pollution from wood-burning plants, and had commissioned the Manomet Study to inform state policy. When the Manomet Study was completed, the state agreed to issue a science-based set of rules eliminating subsidies to the most polluting biomass plants, and the ballot measure was set aside.

Finalized in 2012, the Massachusetts biomass rules became the first in the nation and the world to recognize that burning trees for energy increases emissions just when we should be reducing them. The whole process took about four years, and involved the multi-investigator Manomet study, many public meetings, and thousands of hours of time by citizens and concerned scientists who weighed in to make sure the state’s rules were based in science.

Now, unbelievably, we have to defend those rules, AGAIN – because they are under attack by the Baker administration. DOER is proposing rolling back the rules enacted in 2012, with changes that will lead to more forests being cut for fuel, more CO2 in the atmosphere, and more climate damage. It even seems likely the rule changes will help at least one of the three large biomass plants be built (Palmer Renewable Energy in Springfield.). Adding insult to injury, all of this will come at great cost to ratepayers, who pay millions to support this polluting technology – money that could be allocated instead to residential heating efficiency (nega-watts!) and lower/zero emissions technologies.
The 2012 RPS rules still allowed biomass power plants to get subsidies, but the plants would have to meet strict efficiency criteria, so that only efficient combined-heat-and-power (CHP) plants would qualify, and not the large inefficient electricity-only plants that had been proposed. Biomass power plant operators were required to provide fuel supply plans that would demonstrate they were getting the majority of their fuel from “forestry residues,” not whole trees (see appendix below for why the type of wood matters). The cumulative net carbon impact of biomass power plants had to be 50% that of a natural gas plant after 20 years, which at this point seems absurdly long.

Now, the Baker administration wants to rewrite those rules to make them more favorable to the biomass industry, including weakening and even eliminating plant efficiency requirements, removing fuel supply requirements to allow burning more whole trees, and the requirement to show a “benefit” relative to fossil fuels in 20 years (the Baker administration is changing it to 30 years, because apparently, they know better than the climate scientists, and think addressing global warming isn’t that urgent). They’re also weakening requirements for emissions of “conventional” pollutants (e.g. particulate matter) and removing requirements for citizen oversight and oversight by the MA Dept. of Environmental Protection (DEP), the agency that safeguards our air quality. The rules will even increase subsidies to garbage-burning!

These changes represent a total betrayal of a hard-won compromise and agreement from 2012, to say nothing of the 100,000+ people who signed a petition to take ALL biomass out of the RPS. DOER apparently got an earful from the forestry and biomass industries that the biomass rules were too restrictive – so now they’re rewriting them. (Not unlike the Trump administration, the Baker administration DOER seems to contain people who advocate for the industries they represent, rather than regulating them.)

It’s a similar story with the Alternative Portfolio Standard (APS). After the RPS rules went into place in 2012, and it became clear that the large wood-burning plants would probably not be built, the forestry and biomass lobby went into high gear, and working with DOER, added biomass thermal energy to the APS, which had previously been a catch-all program that provided subsidies to a few technologies that the state wanted to incentivize, but that did not really qualify as “renewable” energy (such as combined heat and power). Along with solar and geothermal heating, biomass heat-only units were made eligible for public subsides (as were biomass combined heat and power plants, just like in the RPS – except the APS contained none of the protective rules the RPS contained. Click here for an overview of the differences between the programs).

It took a few years to get the APS regulations finalized. Scientists and activists fought to keep the APS “clean” by advocating that it only include zero-emissions thermal sources (like solar and geothermal) but the wood industry was powerful, and they got biomass thermal added. It seemed like at every round of public comment, the DOER had further weakened the APS regulations (you can see some of our comment letters here). We ended up with lax regulations that promote the wood fuel that can be the most carbon-intensive – wood pellets. (Click here for a presentation summarizing some of the problems with the APS).

We still don’t know what the final rules will look like once the Baker Administration is done with them. Meanwhile, we should not miss any opportunity to tell them that clean energy doesn’t come out of a smokestack!


Appendix: Net carbon impacts of different types of wood fuel

Determining the carbon impact of burning these for fuel requires comparing the emissions from combustion to the emissions from an alternative fate. The type of wood burned is thus important to the net CO2 emissions impact. There are four main categories of fuel.

Mill residues: wood shavings, sawdust, bark. “Clean” mill residues can be burned directly or made into wood pellets.

  • Mill residues are considered to have relatively low net carbon impact if the alternative fate of this material is to decompose (emitting carbon) or be burned without energy recovery.
  • However, if this material would have been used for some other purpose (e.g. particleboard), then burning it for energy can force the former user to go out and harvest more trees (“leakage”) which increases emissions.

Forestry residues: tree tops and limbs left over after sawtimber harvesting.

  • Forestry residues have been considered to have relatively low net carbon impact if the alternative fate of this material is to decompose. However, the net carbon impact of burning residues is still significant – especially in a world where we want to limit emissions now.  PFPI published a paper on this (and there’s a short video abstract if you’re not in a reading mood) – available here.
  • The relatively low net emissions impact of residues in the Manomet Study and the subsequent regulations by MA means that DOER (and foresters) want to call everything residues. True residues are the by-product of sawtimber harvesting. Cutting trees and calling them “residues,” as the forest industry tends to do, is not legitimate and significantly increases the net emissions impact.

Trees: Whole trees that are cut specifically for fuel, or trees that are “thinned” because now there is a market for the wood.

  • Trees are considered to have the highest carbon impact because if they were not cut and burned for energy, they’d either continue growing and taking carbon out of the atmosphere; OR, they’d be harvested for some other purpose, potentially a long-lived wood product that locks up some of the tree’s carbon away from the atmosphere.
  • And as with mill residues, if the trees would have been used for some other purpose (e.g. pulp and paper) and now they are harvested for bioenergy, that means the paper industry needs to go cut trees somewhere else – hence, more leakage, and more emissions. (Note:  if the paper industry went out of business already, then harvest for paper isn’t the “alternative fate” anymore. Now, the alternative fate is for the forest to continue growing and sequestering carbon. That’s why claims that biomass harvesting is simply taking up the slack from the dying paper industry in New England don’t change the fact that cutting and burning trees means the atmosphere sees more CO2than under an alternative scenario).

Construction and Demolition Debris wood (CDD): This material tends to contain relatively high concentrations of toxics like lead, the pressure-treatment chemicals arsenic and chromium, pentachlorophenol, and other contaminants that are released by burning chemically treated and glued wood.  Proponents of burning this material say it can be sorted to remove the most contaminated materials, but there is no evidence this produces a clean fuel source.

  • In terms of carbon impact, recycling the clean wood rather than burning it would increase carbon sequestration and reduce forest harvesting. Contaminated wood can be landfilled, where it represents sequestered carbon (and is actually counted as such in the US greenhouse gas accounts). Burning contaminated wood, if it must occur, should only be done in incinerators with especially tough emissions controls to help reduce toxic emissions. The biomass industry has fought hard, however, to get contaminated wood classified as “biomass” so that they can burn it anywhere (see our “Trees, Trash, and Toxics” report on the loopholes in air permitting for biomass).

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