Potential for carbon dioxide removal of carbon capture and storage on biomass-fired combined heat and power production

Carbon Dioxide Removals (CDR) and Carbon Capture and Storage (CCS) have received a lot of attention as a tool to mitigate climate change and reach climate neutrality. Bioenergy with Carbon Capture and Storage (BECCS) is seen as one of the more promising CDRs, and from 2026, the Danish utility Ørsted is establishing the first BECCS plants in Denmark. We present a case study of BECCS by installing CCS at a biomass-fired CHP plant and the aim is to quantify the CDR potential and carbon dynamics of the BECCS system. Moreover, the study aims to quantify the emissions related to capturing and store CO₂. The GHG emissions from CCS including heat, electricity, transport and storage are approximately 100 kgCO₂/t stored CO₂ and the carbon payback time of the BECCS system is 3–4 years relative to leaving the wood in the forest or at processing industries. The main driver of the payback time is the additional use of biomass to operate CCS which shifts the timing of CO₂ emissions more towards the present. The additional biomass use also increases supply chain emissions, and on top of that, only 90% of the direct CO₂ emissions from the CHP plant are captured. The study illustrates the importance of temporal scope in assessing the CDR potential of BECCS. With continuous use of biomass, GHG emissions are 207 kgCO₂/t stored CO₂ in year 1 and −742 kgCO₂/t stored CO₂ in year 99. This study reveals inconsistencies in the assessment of the CDR potential of BECCS in the literature. There is a considerable need for further research within this field to assess how BECCS can contribute to mitigating climate change and on the appropriate scale of BECCS deployment.