Feasibility Study of Capture Technology Applied to Small Scale Emitters

Abstract

Carbon Capture, Utilisation, and Storage (CCUS) is widely recognised as a key part of the toolkit of solutions needed to reach net zero greenhouse gas emissions. Up to now, most analysis on the deployment of carbon capture for power and industrial application has focused on large-scale sites. However, a significant share of the emissions from industry and power generation arises from smaller sites, as defined by their level of CO2 emissions. Decarbonisation of such sites will be required to honour the net-zero pledge, which justifies the increased attention to the need to capture CO2 from these sites. This analysis led to the selection of independent thresholds for defining what constitutes a small-scale capture application in (1) Power generation – plants with an unabated installed capacity of up to 100 MWe, and in (2) Industry – sites emitting up to 100 ktCO2/year from point sources. The results show a significant cost escalation when the size of the capture unit is scaled down. Whilst the large-scale NGCC power plant shows the lowest cost of carbon capture ($44/tCO2), the Energy from Waste plant and the lime kiln – the two case studies with the lowest level of unabated CO2 emissions – show a much higher cost of capture, ranging from $90/tCO2 to $103/tCO2. Capital expenditures (CAPEX) are the dominant cost factor at smaller scales. CAPEX represents 37% of the levelised capture costs for a large-scale NGCC power plant, but its importance grows to 49% for its small-scale analogue.

Keywords: CO2 capture, small emitters, NGCC, waste to energy, lime kiln, CHP