The greenhouse gas removal potential of bioenergy with carbon capture and storage (BECCS) to support the UK's net-zero emission target

Abstract

The UK is the first major economy to legislate the reduction of all GHG emissions to net-zero. Greenhouse gas removal (GGR) approaches are likely to be required to support the 2050 net-zero target by offsetting residual emissions from ‘hard-to-abate’ sectors. Bioenergy with carbon capture and storage (BECCS) is investigated as one technical solution for GGR. This research used process modelling and lifecycle assessment to identify the GGR potential of three BECCS supply chains. Results show that the BECCS supply chains have significant GGR potential with net-negative emissions as CO2e between −647 and −1137 kg MWh−1. Emissions were compared per unit energy output, biomass and area required for each supply chain to assess the GGR potential and BECCS sustainability implications. The large-scale BECCS supply chain features robust technologies with high capacity factor. It produces the greatest electricity generation and annual GGR, however, demands large amounts of biomass raising potential sustainability issues. The medium-scale (CHP) BECCS provides the greatest GGR potential per energy due to its higher energy efficiency. Limitations are a low capacity factor, energy demand-supply balance and non-existent decentralised CCS infrastructure. The (hydrogen) BECCS supply chain is more versatile, producing hydrogen with the potential to support the decarbonisation of not just power, but heat and transport sectors. The GGR potential sits in the middle and has greater benefits from a biomass sustainability perspective, yet, hydrogen infrastructure is not established, and costs remain uncertain. The relative performance of alternative BECCS supply chains should consider direct links between CO2 removal and sustainable biomass and land use, as well as GGR potential.