The role of bioenergy with carbon capture and storage in the UK’s sustainable future

This report describes a workshop at the Royal Society that brought together a diverse mix of experts from different sectors to explore The Role of Bioenergy with Carbon Capture and Storage (BECCS) in the UK’s Sustainable Future, with a focus on the potential sustainability of different feedstocks. The workshop aimed to provide an independent forum for participants to explore the key areas of agreement, disagreement and knowledge gaps across the community. This report summarises the workshop discussions but is not a detailed evidence review. While participants offered a range of views, most agreed that BECCS has the potential to deliver negative emissions but that this was highly case-specific, and some were also concerned that the full life-cycle emissions and removals over time are not always clearly reported in climate models and national carbon accounting frameworks. There were mixed views on the use of unabated bioenergy combustion for power generation, with most agreeing that this is not a good use of limited biomass resources and should only be considered for genuine waste feedstocks with no alternative uses. Several significant concerns were highlighted, mainly around the use of forest biomass, the dominant BECCS feedstock, and particularly if scaling-up led to increased extraction of biomass from biodiverse natural forests (as planned in the US and UK) rather than from plantations. Issues included the carbon balance (long payback periods for wood pellets from some sources), biodiversity impacts (including legal felling of old-growth forest for biomass), contradictory evidence on the impacts of forest biomass extraction on fire risk, competing uses of land and resources (including for higher value bioeconomy products), and social impacts on vulnerable local communities. Most participants viewed feedstocks such as waste and domestically produced short-rotation coppice or energy grasses such as miscanthus as potentially more sustainable, though with some questions around the impacts and feasibility of scaling-up. As a result, many voiced strong concerns that current evidence on sustainable biomass supply does not support BECCS deployment at the scales implied by the CCC’s 6th Carbon Budget and heavily BECCS-dependent climate-economic Integrated Assessment Model (IAM) scenarios. There were different views on whether the risks and uncertainties raised are relatively minor in the context of the need for BECCS in climate strategies, and are already being overcome; or whether they represent severe threats to biodiversity that inherently limit sustainable deployment of BECCS to low levels. A deeper exploration of systemic impacts and decision-making in the context of these far-reaching uncertainties and different priorities and concerns could be useful.