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Academies of Sciences identify strategies for the sustainable use of bioenergy

27. May 2019

As the most diverse form of renewable energy, bioenergy can help us achieve the necessary reduction in climate emissions. However, for this to be possible it will need to be produced and utilised more sustainably than is currently the case. This is the conclusion reached by the joint Academies' Project “Energy Systems of the Future” (ESYS) in its Position Paper. The paper recommends that more bioenergy should be produced from residues and waste and that it should primarily be used for fuel production and process heat generation in industry. At the same time, research should be carried out into new climate protection solutions such as carbon capture technology in conjunction with bioenergy production.

Increasingly, climate models indicate that replacing fossil fuels with renewables and reducing greenhouse gas emissions will not be enough to prevent climate change. The IPCC has concluded that it will also be necessary to capture and store carbon dioxide from the atmosphere. This view is endorsed by the Federal Ministry for the Environment in the latest draft of the Federal Climate Protection Act, which states that by 2050 any remaining greenhouse gas emissions should be compensated for by the removal of greenhouse gases from the atmosphere. One option would be the capture and underground storage of the CO2 produced during the conversion of biomass into bioenergy (BECCS).

A working group of the joint Academies' Project “Energy Systems of the Future” (ESYS) has investigated how this most diverse form of renewable energy can be produced sustainably and utilised optimally in the context of the overall energy system, thereby contributing to climate protection. The Position Paper “Biomass: striking a balance between energy and climate policies” summarises the policy options formulated by acatech – National Academy of Science and Engineering, the German National Academy of Sciences Leopoldina and the Union of the German Academies of Sciences and Humanities. The academies identify a number of ways of promoting sustainable bioenergy use that contributes to climate protection.


Negative emissions as a key to climate protection

BECCS is not the only way of capturing CO2 from the atmosphere. Alternatives include reforestation, biochar and direct air capture, where carbon dioxide is extracted from the atmosphere. ESYS working group co-chair Gernot Klepper (Kiel Institute for the World Economy – IfW) explains why the Federal Government should seriously consider including these solutions in its climate action strategy: “Germany will have a far slimmer chance of meeting its climate targets unless it generates negative emissions by removing CO2 from the atmosphere. We must carry out more research into these technologies in order to thoroughly assess their potential for deployment.” He adds that public acceptance of controversial CCS technology will be paramount. ESYS recommends bringing all the stakeholders together in a platform in order to promote a broad public debate.

Making greater use of residues and waste

Leaving BECCS to one side, there are many different ways of using bioenergy. However, land use conflicts are becoming more common as the global population grows, while further agricultural intensification will have implications for the environment. There is thus a danger that bioenergy produced from timber and agricultural raw materials may not be sustainable. Consequently, most bioenergy should be produced from residues and waste. This form of bioenergy could cover between 13 and 17 percent of Germany’s primary energy needs by 2050.

Bioenergy for fuel and process heat

ESYS recommends the use of biomass in those parts of the energy system where other renewables are reaching their limits. For instance, the production of climate-friendly fuels from biomass is much more efficient than using wind and solar power. “In the long-term, we hope that bioenergy will be used to produce fuel for aviation, shipping and heavy goods vehicles, since it is unlikely that we will be able to use electricity to power these forms of transport. Another area where it would make sense to use bioenergy would be in industrial facilities that require high process temperatures – bioenergy sources are perfectly capable of generating these temperatures”, explains Daniela Thrän of the Helmholtz Centre for Environmental Research and the Deutsches Biomasseforschungszentrum, who co-chaired the ESYS working group with Gernot Klepper.

Using the CO2 price as a control mechanism

ESYS recommends the use of a sufficiently high, global CO2 price as a control mechanism that acts as an incentive for the climate-friendly production and utilisation of bioenergy. Ideally, the CO2 price should apply to all greenhouse gases in all sectors of the economy, including emissions from agriculture. Until a global CO2 price is introduced, certification of biomass imports can help to deliver minimum CO2 savings and meet other sustainability criteria. However, in order to prevent further global deforestation, these rules should apply to all agricultural and forestry products, not just bioenergy.

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