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“If this regulation becomes established practice, this would consume quantities of wood equal to all Europe’s wood harvests, greatly increase carbon in the air for decades, and set a dangerous global example,” says Wolfgang Lucht from the Potsdam Institute for Climate Impact Research, who’s one of the authors of the analysis. The researchers estimate that the new regulation would turn a projected 5 percent decrease in emissions into a 5 to 10 increase by using wood. What is worse, other countries might do the same.

This could substantially affect forests around the world. “Globally, if the world were to supply only an additional 2 percent of its energy from wood, it would need to double commercial wood harvests around the world with harsh effects on forests,” said study lead author Tim Searchinger, research scholar at Princeton University’s Woodrow Wilson School of Public and International Affairs.

Although wood is renewable, cutting down and burning it for energy increases carbon in the atmosphere for decades, the researchers explain. Bioenergy use in this form takes carbon that would otherwise remain stored in a forest for an extended period of time and puts it into the atmosphere. Because of inefficiencies in the harvesting and burning process, the result is that more CO2 is emitted into the air per kilowatt hour of electricity or heat than burning fossil fuels, the authors explained - while regrowing trees can eventually reabsorb the carbon, they do so slowly and, for years, may not absorb as much carbon as the original forest would have absorbed. Because the processes involved are slow, climate benefits of this form of biomass use would occur only after nearly a century.

“We should not treat the biosphere as if it were a disposable resource. It makes no sense to recycle paper to save wood or to support global reforestation and then expand greatly the burning of trees for energy. That is neither green nor sustainable nor climate-friendly. Regulation has to achieve the right design to ensure the  important goal of stabilizing climate,” says Lucht. “Science can help to detect unintended side-effects and identify sustainable pathways.”

Article: Timothy D. Searchinger, Tim Beringer, Bjart Holtsmark, Daniel M. Kammen, Eric F. Lambin, Wolfgang Lucht, Peter Raven, Jean-Pascal van Ypersele (2018): Europe’s renewable energy directive poised to harm global forests. Nature Communications [DOI:10.1038/s41467-018-06175-4]

Weblink to article: https://www.nature.com/articles/s41467-018-06175-4