The role of energy supply in abatement cost curves for CO2 capture from process industry – a case study of a Swedish refinery

Artikel i vetenskaplig tidskrift, 2022

Carbon capture and storage (CCS) activities need to be ramped up to meet the climate crisis. Abatement cost curves help identify low-cost starting points and formulate roadmaps for the implementation of CCS at industrial sites. In this work, we introduce the concept of energy supply cost curves to enhance the usefulness and accuracy of abatement cost curves. We use a multi-period mixed-integer linear program (MILP) to find an optimal mix of heat sources considering the existing site energy system. For a Swedish refinery, we found that residual heat and existing boiler capacities can provide the heat necessary for CCS that avoids more than 75% of the site emissions. Disregarding the existing site energy system and relying on new capacities instead, would lead to capture costs that are 40-57% higher per tonne of CO2-avoided (excl. CO2 liquefaction, transport, and storage). Furthermore, we quantified the impact of temporal variations of heat sources (intermittent residual heat) on the cost and emissions of heat supply to 7-26% and 9-66%, respectively. The conducted optimization of the energy supply mix under consideration of temporal variations leads to detailed estimates of energy supply costs ranging from partial to full CO2 capture, and thus, improve abatement cost curves.