Biomass industry lobbyists took a serious body blow yesterday as the state of Massachusetts proposed final rules modifying its Renewable Energy Portfolio Standards that would bring some much need integrity to renewable energy policy. The proposed changes were aimed directly at reforming provisions governing burning wood in biomass power plants. They are the penultimate step in codifying the conclusions of the path-breaking Manomet Study which found that tree-burning power plants are major carbon polluters.
While not perfect, these regulations represent a profound and potentially pivotal victory for science-based policy on biomass energy. Kudos to Massachusetts regulators. If finalized, the rules will require for first time anywhere in the world, that renewable energy credits for biomass energy be granted based on a common sense, life cycle assessment of the carbon emissions of burning forest wood to generate electricity.
Massachusetts' Global Warming Solutions Act requires that the state reduce greenhouse gas emissions 25 percent below 1990 levels by 2020, and by 80% by below 1990 levels by 2050. Ratepayers pay extra on their electric bills to fund renewable energy, on the assumption that promoting “carbon free” electricity generation will help the State meet its greenhouse gas reduction goals, as well as increase energy independence.
The new biomass regulations thus require that biomass energy generation actually reduce carbon emissions over a reasonable time period, beginning today, if it is to be considered renewable. Facilities that don’t meet the standard are ineligible for renewable energy credits for electricity generation.
And that standard is emminently reasonable. To earn ratepayer subsidies, biomass burners must show that they produce no more than 50 percent of the greenhouse gas emissions from a new natural gas facility, over a 20-year period. This isn’t just reasonable, it is quite generous. The standard does not require anything close to zero carbon emissions from biomass burners, it simply ensures that the facility actually emit less greenhouse gas emissions than a fossil fueled facility, so that ratepayer-funded renewable energy credits only go to those power sources that help the state meet its renewable energy goals.
For the biomass power industry this is a disaster. The science is unequivocal: burning trees to generate electricity produces 3 – 4 times more CO2 pollution than natural gas, and 50 percent more than coal, per unit of electricity generated. Even when the carbon captured from the atmosphere and stored in trees during regrowth is considered, it takes more than 90 years for biomass energy fueled by whole-tree harvesting to achieve carbon parity with natural gas. And that’s just parity. It would take well over a century to achieve 50 percent less carbon emissions than natural gas, far beyond the 20-year requirement proposed in the regulations.
Why 20 years, your might ask? The point of all this is to reduce global warming pollution from the energy sector. We need to reduce those emissions today, not 100 years from now. Burning trees to generate electricity will actually accelerate climate disruption for the next 40 to 100 years, right when we need to be headed in the other direction. No sane, science-based renewable energy policy would subsidize that.

Of course the proposed final regulations have some problems, including unnecessarily slippery language that could allow too much burning of forestry residues, the tops and branches that when left behind preserve soil fertility and protect against erosion. Forestry and biomass industry pressure was felt in the Massachusetts rule-making process, too. But on balance, these regulations are a watershed, and when finalized, may be the shot heard round the world for renewable biomass energy.