Decision making beyond models of bioenergy with carbon capture and storage

Licentiate thesis, 2025

Although bioenergy with carbon capture and storage (BECCS) is a prominent CO₂ removal technology in global climate mitigation models, its deployment remains limited. To understand how BECCS could be scaled up beyond models, I identify key investment conditions for prospective BECCS actors in Sweden, including operators of combined heat and power (CHP) plants and pulp mills. Using robust decision making (RDM) methods, I combine the analytical strengths of models and actors to characterize investment decisions that are robust across uncertain scenarios. I find that actors need to exercise political power beyond their normal system boundaries to effectuate policies and discourse supportive of BECCS. Across most scenarios, the CHP actor Stockholm Exergi was found to require 151 EUR/tCO₂ from voluntary carbon markets. In practice, they may have secured higher market revenues plus subsidies at 160 EUR/tCO₂. Similarly, the CHP actor E.ON could require market revenues above 185 EUR/tCO₂ and subsidies at 160 EUR/tCO₂ to enable a robust investment. For CHP plants, incentives from the European Emissions Trading System could be insufficient unless allowance prices rise sharply or BECCS credits are integrated into the system through public procurement. Furthermore, actors should assess the capital costs of oxyfuel and chemical looping rigorously: If these capital costs are low, actors may regret opting for more mature capture technologies. Finally, BECCS actors need to utilize bioenergy responsibly, for example by recovering energy from industrial residues where biomass is sourced from biodiverse and net-negative forest. About 19 MtCO₂ p.a. could be captured from 113 existing bioenergy plants without sourcing any additional biomass, while the associated costs and CHP penalties could be constrained by efficient heat integration choices.