“In the medium term, within a time scale of decades, forests will not have sufficient time to capture back enough of the carbon dioxide that gets released into the atmosphere when producing energy. Consequently, increased use of bioenergy will jeopardise the climate goals set by the UN, according to which the world should be carbon-free by mid-century,” says Atte Korhola, professor of environmental change at the University of Helsinki and one of the authors of the recently published article by the researcher group.
According to the research group, the energy density of forest-based biomass is already so low to begin with that it will not be suitable for replacing fossil energy. Carbon dioxide emissions of biologically produced energy in relation to the amount of energy produced are clearly higher than those of coal, the worst climate polluter.
In fact, the researcher group is demanding that the classification of bioenergy be reconsidered and the concept of carbon neutrality be abandoned. According to the survey, only bioenergy derived from the branch currents of industry fulfil the requirements of carbon neutrality, but only with certain provisions. If logging and preparation of the forest soil increase, the waste-based forest energy will also lose its climate benefits.
The concept of carbon neutrality is based on a notion according to which growing forests capture back the carbon dioxide emitted when burning. However, numerous studies show that this ‘payback’ takes considerably longer than what was earlier believed. It is a question of decades or even of centuries. Depending on the harvesting practices, the carbon reservoir of forestland may be left entirely unrestored.
Favouring bioenergy does not promote curbing the rise of the Earth’s average temperature
The research group feels that favouring bioenergy will backfire, in particular with regard to the goals aiming to keep the rise of the Earth’s average temperature below 1.5 degrees Celsius. According to the Intergovernmental Panel on Climate Change (IPCC), at the current rate, the critical limit will be reached by 2030–2050, which means that the utilisation of forest-based biomass for energy production will definitely not have enough time to be compensated for in the form of growing forests.
Favouring bioenergy may also increase the logging cycle, which already is way too short in many countries. According to Korhola, also in Finland the logging cycle has shortened in recent years, and way too young state-owned forests are clear-felled.
“The situation is even less beneficial when the entire life cycle of wood biomass production is taken into account. In addition to actual burning, emissions are created by harvesting, raw material transport and processing,” says Korhola.
Wood biomass pellets are already transported in international markets to the volume of more than 10 million tons a year, primarily between the United States and Europe but increasingly also in Asia.
The peer-reviewed joint publication was written by researchers belonging to the environment programme of the European Academies’ Science Advisory Council EASAC. The authors of the paper include Professor of Environmental Change Atte Korhola from the Faculty of Biological and Environmental Sciences at the University of Helsinki. EASAC is formed by the national science academies of the EU member states, Norway and Switzerland and aims at providing independent scientific advice to European policy-makers.
Norton, M., Báldi, A., Carli, B., Cudlin, P., Jones, M., Korhola, A., Michalski, R., Novo, F., Duarte S.F., Schink, B., Shepherd, J., Vet, L., Walloe, L. & Wijkman, A. 2019. Serious mismatches continue between science and policy in forest bioenergy. Global Change Biology: Bioenergy. https://doi.org/10.1111/gcbb.12643