Carbon accounting used in the Kyoto Protocol and other climate legislation currently neglects CO2 emissions from the production of biofuels, a loophole that could drive large-scale destruction of tropical forests and exacerbate global warming, warned researchers writing last week in the journal Science.
Jerry Melillo and a dozen co-authors noted that the Kyoto Protocol, the European Union’s cap-and-trade law, and the American Clean Energy and Security Act all fail to account for emissions resulting from production and use of biofuels. Instead the carbon accounting systems erroneously assume that biofuel production is carbon neutral. In reality, establishing bioenergy crops in place of carbon-dense ecosystems like tropical rainforests and peatlands results in substantial greenhouse gas emissions.
“When forests or other plants are harvested for bioenergy, the resulting carbon release must be counted either as land-use emissions or energy emissions,” said Melillo in a statement. “If this is not done, the use of bioenergy will contribute to our greenhouse gas problem rather than help to solve it.”
Chart modified from Science. A February 2007 study published in Science showed that production of some biofuels can result in emissions greater than those from fossil fuels. The analysis looked at the lifecycle emissions from various biofuel feedstocks and presented the results as a “carbon debt” ranking.
The authors urge policymakers to fix the the accounting flaw by establishing a system that counts all emissions, whether from fossil fuels or bioenergy. They system should also include other greenhouse gas emissions associated with bioenergy production and use, like methane and nitrous oxide.
“Bioenergy has the potential to provide a substantial amount of energy and help nations meet greenhouse caps, but correct accounting must be in place to prevent unintended consequences of unsustainable bioenergy production,” said Melillo.
“As we approach the most important climate treaty negotiations in history, it is vital that technologies, such as biofuels, that are proposed as solutions to global warming, are properly evaluated,” said co-author Daniel Kammen, a University of California, Berkeley, professor of energy and resources and of public policy. “Our paper builds on recent work on the direct and indirect land use impacts of biofuels, and clarifies how the accounting should be done.”
CITATION: Melillo et al. Indirect Emissions from Biofuels: How Important? Science 22 October 2009.
(07/16/2009) Sustainable biofuels can be a reality but only in combination with reductions in fuel demand and increased productivity on existing agricultural lands, argue researchers writing in the journal Science. Five years ago biofuels were seen as a panacea for the world’s energy hunger and the need to address climate change, but increased production of biofuels soon contributed to a clutch of problems, including competition with food, resulting in rising prices, and large-scale conversion of rainforests and tropical grasslands for feedstocks, resulting in biodiversity loss and increased greenhouse gas emissions. Environmentalists and scientists condemned many biofuels — including ethanol produced from Midwestern corn ethanol and biodiesel generated from European rapeseed and Southeast Asian palm oil — as a short-sighted energy solution. Some biofuels were found to be even worse for the environment, and more costly, than conventional gasoline. However some researchers remain optimistic that smart biofuel production could help meet energy demand without hurting people or the planet. In a Science Policy Forum piece, David Tilman and colleagues explore some of these options, noting that biofuels can be produced in substantial quantities at low environmental cost
(08/27/2008) The British government should end subsidies for biofuels and instead use the funds to slow destruction of rainforests and tropical peatlands argues a new report issued by a U.K.-based think tank. The study, titled “The Root of the Matter” and published by Policy Exchange, says that “avoided deforestation” would be a more cost-effective way to address climate change, since land use change generates more emissions than the entire global transport sector and offers ancillary benefits including important ecosystem services.
(07/22/2008) Biofuels meant to help alleviate greenhouse gas emissions may be in fact contributing to climate change when grown on converted tropical forest lands, warns a comprehensive study published earlier this month in the journal Environmental Research Letters. Analyzing the carbon debt for biofuel crops grown in ecosystems around the world, Holly Gibbs and colleagues report that “while expansion of biofuels into productive tropical ecosystems will always lead to net carbon emissions for decades to centuries… [expansion] into degraded or already cultivated land will provide almost immediate carbon savings.” The results suggest that under the right conditions, biofuels could be part of the effort to reduce humanity’s carbon footprint.
(06/14/2008) The emergence and expansion of biofuels produced from food crops has exacerabted world’s agriculture and water crisis and is a bigger short-term threat than global warming, argued Peter Brabeck-Letmathe in an editorial published Thursday in the Wall Street Journal Asia.
(05/27/2008) Next generation biofuels could decimate tropical forests says a leading ecologist from the University of Minnesota.
(01/03/2008) Biofuels made from world’s dominant energy crops — including corn, soy, and oil palm — may have worse environment impacts than conventional fossil fuels, reports a study published in the journal Science.