Regretting carbon capture from bioenergy – A case study

Both deploying and not deploying carbon capture and storage (CCS) may lead to regret, be it in terms of climate damage, carbon revenues, or sociopolitical impacts. To support robust decision making (RDM) on CCS, our study aims to identify high-regret scenarios of a bioenergy CCS (BECCS) investment decision by E.ON in Malmö, Sweden. Across 1.000.000 input scenarios, regret is quantified as the difference in net present value between deploying amine CCS and three alternative decisions: no CCS, oxyfuel CCS, or chemical-looping CCS. Scenarios of positive regret are thus undesirable and of interest, and were identified using data mining. Amine CCS is regrettable relative to no CCS in 90 % of scenarios if CO2 removal revenues – excluding subsidies – fall below 220 EUR/tCO2. Relying on revenues from the European Union Emissions Trading System is only robust if removals are integrated into the system through public procurement. In revenue scenarios above 285 EUR/tCO2, amine CCS is robust and the no CCS decision leads to regret in 75 % of cases. Contrastingly, amine CCS leads to regret relative to oxyfuel when oxygen separation is inexpensive, and relative to chemical-looping when its capital cost is not unexpectedly high. Alternative capture technologies could therefore enable low-regret CCS if cost uncertainties were reduced.