Assessment of selected CCS technologies in electricity and synthetic fuel production for CO2 mitigation in South Africa

One of the actions proposed to reduce greenhouse gas (GHG) emissions in South Africa (SA) is to install carbon capture and storage (CCS) at new energy-producing plants. This paper aims to evaluate the costs and GHG emissions of implementing CCS at a coal-fired integrated gasification combined cycle (IGCC) power plant, at a coal fired ultra-supercritical (USC) power plant, at a synthetic fuel coal-to-liquid (CTL) plant and at a gas-to-liquid (GTL) plant for SA. The approach for comparing of these CCS applications is based on a combination of a techno-economic analysis with a life-cycle assessment. As expected, the generating costs in plants with CCS are higher than without CCS for all case studies. GHG-abatement costs in 2040 are shown to be the lowest for the IGCC power plant at 173 ZAR07/t CO2eq, followed by the USC power plant at 227 ZAR07/t CO2eq. These costs are considerably higher for the CTL and GTL plants. The results show that from an economic perspective, CCS might be an attractive option for CO2 mitigation in SA especially for the electricity sector. However, a prerequisite for the implementation of CCS is that the technology reaches commercial scale for the investigated options and is socially accepted.