Magically carbon neutral biomass, evil EPA rules and other myths

Wouldn’t it be great if you had a bank account that automatically filled back up no matter how much you spent? You could just ignore how much you spent. Amazingly, the bioenergy industry has succeeded so far in convincing legislators here in the U.S. and around the world that bioenergy offers just such a carbon account. According to the industry, we only need to look at the carbon that biomass absorbs, not the carbon emissions it releases. The industry has convinced policymakers that no matter how much carbon is “spent” when biomass is burned for energy, there will magically be enough income in the form of regrowth to cover all expenses. Because of this magic, the industry would have us categorically exclude their emissions when we do our carbon accounting.

As I've written about before, both the House climate and energy bill (ACES) and the American Power Act recently introduced in the Senate buy into this magically carbon neutral source of energy. The European Union has done it too.

So how did the biomass industry and its supporters on Capitol Hill react recently when EPA said it was going to account for the emissions column of the ledger as part of its rules governing which facilities will be covered by the Clean Air Act? Sadly, with willful misinterpretation. The industry and its supporters have been able to cow the agency and the rest of Congress by claiming that EPA is only going to look at the emissions associated with burning biomass. Only looking at the expenses part of the ledger would be just as wrong as assuming magical income, but that of course is not what EPA said it would do.

Back middle of May, EPA released its "tailoring rule," which governs which sources of global warming pollution will be required to get federal pollution permits. The rule includes the smokestack pollution from burning biomass. The preamble to the rule discusses some of the complexity around biomass emissions accounting and announces EPA's intention to seek stakeholder input and, within a year, issue guidance on how to account for both sides of the ledger.

On May 24, Weyerhaeuser—one of the biggest proponents of the concept that bioenergy is magically carbon neutral—sent EPA a letter saying that it was "taken aback" that EPA wasn't towing the line, buying into the magic, and ignoring biomass emissions.

On June 2, EPA responded to Weyerhaeuser by pointing out that it was already committed to getting input and working to get biomass accounting right. That would be the end of a wonky story except that last week the Senate considered (and fortunately rejected) a proposal from Senator Murkowski that would have forced EPA to stop this work and ignore all sources of global warming pollution. What’s more, some Senators that should have known better thought that this was a way to "fix" EPA's tailoring rule.

As my colleague Dan Lashof wrote, Senators Collins and Snowe from Maine and Senator Brown from Massachusetts voted last week for Murkowski's massive giveaway to coal and oil--because as Senator Collins put it:

“Incredibly, the EPA proposes to ignore the carbon neutrality of biomass and place onerous permitting requirements on businesses such as Maine's biomass plants and paper mills, which use biomass to provide energy for their operations.”

Interestingly, the same day that the Senate was voting to reject Murkowski's big polluter bailout, Massachusetts was releasing a report commissioned by the state's Department of Energy Resources. As I've written a little about, this report, done by Manomet Center for Conservation Sciences, makes it very clear that most forest biomass is not carbon neutral. In fact, the report finds that burning whole trees to make power would leave the atmosphere 3% more polluted between now and 2050 than burning coal over that same period.

This finding should not be surprising. Wood, especially green wood, contains less energy per pound of carbon than coal and forests grow slowly. So when we burn a tree, we're releasing more carbon and getting less energy than we would if we burned coal, and then re-absorbing that carbon very slowly as trees grow back. This means the timeframe over which we do our accounting also makes a big difference. For example, over 100 years or more, the forest may grow back, reabsorb the carbon that we released initially, and possibly absorb enough additional carbon to put the biomass carbon ledger ahead of coal, but there’s no guarantee. And in the meantime the climate get more and more unstable and 100 years is simply too long to wait for significant carbon reductions.

But the report also discusses how different sources of biomass and different approaches to managing forests after biomass is harvested can have a big impact. Under a best-case scenario for sourcing and forest management, the study finds that 40 years of wood-derived power could actually be 11% better than 40 years of coal. This is still very far from 100% better, which is what carbon neutral implies, but this is why EPA should be netting carbon debits and credits over some reasonable period, and taking into account both the source of biomass and land management practices. I've written about the importance of getting this type of accounting right before and just recently 90 scientists called on Congress to get it right in climate legislation and energy policy.

While the report does an impressive job of looking at a range of forest sourcing scenarios, it doesn't look at woody residues at lumber yards or papermills, where biomass is coming out of forests anyway. Nor does the report try to look at agricultural residues or biomass specially grown on degraded lands. If EPA does netting right, these sources of biomass will be encouraged.

Representing as they do a state with such a strong forest industry, it certainly makes sense for Senators Collins and Snowe to be pushing for smart netting as part of EPA's tailoring rule, but supporting Senator Murkowski's attempt to roll back EPA authority to protect our air quality was not a vote for thoughtful regulation. It was like using a chainsaw where pruning shears would have done the trick, and Senators Collins and Snowe, both leaders in the climate debate, know better.

The second EPA action that Senator Collins takes exception with in her statement is the agency's proposed new air regulations that would require biomass combusters not to emit more carbon monoxide, mercury and other toxics than the cleanest fossil fuel boilers. Tellingly, the industry doesn't argue (subscription required) that they aren't emitting this pollution or that the pollution isn't hurting people's health or even that the technology doesn't existing to clean up the pollution. Their only argument is that it will cost them too much. As Jane Williams, Chairwoman of the Sierra Club's National Air Toxics Task Force, put it: "What they're saying, apparently, is: 'We're just too dirty…We can't meet the standards because we're too dirty.'"

The worst part about this is that bioenergy doesn't have to be a major source of pollution. There are sources of biomass that can be used to replace fossil fuels and provide a low-carbon source of energy. And the toxics that are produced from burning clean biomass are technically easy to control. (Burning garbage, which sometimes gets called biomass, is a different matter.)

But you can't fix a problem if you won’t acknowledge it exists. The ultimate solution is a comprehensive climate and energy bill that requires careful accounting of all carbon, including the carbon released and absorbed by biomass. I hope that Senators Collins, Snowe and Brown will read MA's new report, recognize that carbon neutrality is a myth and biomass pollution is still pollution, and work with NRDC to shape the climate and energy bill and EPA's rules to get the best performance we can out of bioenergy.

About the Authors

Nathanael Greene

Director, Renewable Energy Policy, Energy & Transportation program

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