Fig. 6: Heat maps of cost-optimal configurations.
From: Diversity of biomass usage pathways to achieve emissions targets in the European energy system
Heat maps show cost-optimal configurations for achieving a net-negative (−110%) emissions target when varying upstream emissions of biomass imports (x axis) and allowed annual carbon sequestration potentials (y axis). Upstream emissions equivalent to 10% of the biomass CO2 emissions at full combustion corresponds to 10.3 g CO2 MJ−1. For reference, estimated nitrous oxide emissions from fertilization correspond to 0.4–14 g CO2 equivalent MJ−1 for poplar or willow depending on yields and soil conditions, and, for example, substantially more for rape seed147. Fossil fuels in this analysis are not assumed to entail upstream emissions, which presents an optimistic case for their performance. a,c, Total (a) and imported (c) biomass usage. b, Biomass usage for biofuels. d–g, Least-cost deployment of BECC (d), DAC (e), fossil and cement carbon capture (CC) (f) and total carbon capture and DAC (g). h, The system cost increase of excluding biomass (except municipal solid waste) compared to the least-cost solution for all combinations of carbon sequestration capacity and upstream emissions of biomass imports. i, Fossil fuel usage.
