Biomass is currently the EU’s largest, but oft neglected, renewable energy source, but an analysis led by Chalmers University of Technology in Sweden shows that biomass could be crucial for EU climate targets.

If biomass were excluded from the EU energy system, it would cost an extra €169bn per year – about the same as the cost of excluding wind power.

In addition, biomass can play a key role in an increasingly important part of the climate transition: carbon dioxide removal from the atmosphere, via carbon capture and storage (CCS). The carbon atoms in biomass have been absorbed from the air through plant photosynthesis. Normally, when biomass is used for energy the carbon atoms are released back into the air as carbon dioxide. But when bioenergy is combined with CCS, those carbon dioxide emissions are avoided. Biomass use with CCS therefore provides energy along with carbon dioxide removal from the atmosphere, which is known as negative emissions.

In a paper in Nature Energy, researchers at Chalmers University of Technology, Rise Research Institutes of Sweden and Technische Universität Berlin have carried out a comprehensive analysis and shown what a future energy system could look like – including electricity, heating, industry and transport.

The researchers investigated two emissions targets for the energy system; one with zero emissions of carbon dioxide and one with negative emissions (minus 110 per cent compared to 1990). The biomass in the system consists mainly of waste material from forestry and agriculture within Europe, plus a more expensive part which can be imported.

The study's lead author Markus Millinger, a researcher at Chalmers when the study was conducted and now a researcher at Rise, noted that biomass plays an unexpectedly important role in the energy transition: “One thing that surprised us was how quickly it becomes very expensive if we reduce the availability of biomass in the energy system, due to the high costs of alternatives. If biomass is completely excluded, the costs of the energy system with negative emissions would increase by €169bn annually, compared to the same system with a cost-optimal level of biomass. This is an increase of 20 per cent, which roughly corresponds to the cost of excluding wind power.”

He continued: “But the financial part is perhaps not the largest problem. The big difficulty may be to scale up the alternatives. Even with biomass in the system, it is a real challenge to expand fossil-free energy to the extent needed. Further restrictions on the supply of biomass would make the energy transition very difficult, as even larger amounts of other types of fossil-free energy would be needed.”

---