Biomass: Scientists urge EPA to withdraw GHG exemption plan

Source: By Inside EPA • Posted: Tuesday, February 10, 2015

Dozens of climate scientists are urging EPA to withdraw its recent plan to exempt greenhouse gas emissions due to biomass generation from its rule regulating the emissions at existing power plants, charging the plan is scientifically flawed and will set a bad global precedent for how to address the issue.

“Because EPA can expect its [biomass GHG] accounting rule to be applied globally, it is likely to lead to the additional harvest or conversion to agriculture of large areas of the world’s forests,” says the Feb. 9 letter, which was signed by 78 scientists.

The scientists are targeting a Nov. 19 memo signed by acting air chief Janet McCabe that said the agency will allow states to rely on biomass from undefined “sustainable” practices to be used as a way to comply with the agency’s proposed existing source performance standards (ESPS).

At the same time it issued the memo, EPA released a revised draft biomass accounting framework that will undergo a second review by the Science Advisory Board, which soundly criticized the initial framework in a prior review.The new framework lays out a series of formulas to determine whether biomass carbon dioxide emissions are completely carbon neutral, the degree to which they must be counted, or whether they result in a net emissions cut. EPA also announced its intent to soon propose a rule exempting waste- and sustainably-derived biomass from best available control technology requirements in stationary source permits.

McCabe’s announcements were applauded by the industry and labor groups, which have long urged the agency to accept the notion that combustion of biomass for power generation is carbon neutral because regrowth sequesters any GHG emissions.

Environmentalists, however, say some materials burned for energy — such as whole trees — are worse for the climate than burning coal because of a dramatic immediate release of GHGs that takes decades to resequester.

Many environmentalists have derided the proposed regulatory exemption, warning that the agency appeared ready to take the policy steps regardless of what the SAB says about its second attempt at a framework.

Now, the 78 scientists are weighing in on the matter, noting that the agency’s policy memo is “in conflict with a growing body of peer-reviewed science showing that certain forms of biomass, such as whole trees, significantly increase the release of carbon to the atmosphere.” The letter adds that the SAB’s initial concerns and recommendations “are not addressed in the McCabe memo,” and the scientists fear that the current framework “once again fails to effectively assess the climate impacts of biomass energy production.”

The letter says that burning biomass “does not reduce the carbon emitted by power plants. In fact, as EPA itself acknowledges, burning biomass degrades facility efficiency and increases day-to-day over emissions when fossil fuels are burned alone.”

And it says the potential impacts of the proposed exemption in the ESPS “are large because even small quantities of bioenergy require large quantities of wood.” For example, if biomass supplied 4 percent of domestic electricity, that would require an increase to 70 percent of the timber harvest, which “for perspective would be far greater than if we were to abolish all paper and cardboard recycling” in the country, the scientists say.

The also warn the “exemptions in the McCabe memo are likely to lead to increased U.S. emissions of CO2” because they would “in effect, allow power plants and factories to ignore the loss of carbon from forests when they harvest trees for energy, but the U.S. must count this carbon when it reports national emissions under the U.N. Framework Convention on Climate Change. . . . Ignoring this carbon in U.S. law cannot change what the atmosphere sees, and does not change our obligation to report those emissions accurately to the world.”

Finally, they say the approach would undercut efforts to promote truly low-carbon biomass because power producers would have little incentive to focus on wastes and residues.

Scientists signing the letter include Ken Caldeira of the Carnegie Institute of Washington, Tim Searchinger of Princeton University, and William Schlesinger and Norm Christensen of the Nicholas School of the Environment at Duke University, among others.