Techno-economic appraisal of fossil-fuelled power generation systems with carbon dioxide capture and storage

Carbon capture and storage (CCS) facilities coupled to power plants provide a climate change mitigation strategy that potentially permits the continued use of fossil fuels whilst reducing the carbon dioxide (CO2) emissions. This process involves three basic stages: capture and compression of CO2 from power stations, transport of CO2, and storage away from the atmosphere for hundreds to thousands of years. Potential routes for the capture, transport and storage of CO2 from United Kingdom (UK) power plants are examined. Six indicative options are evaluated, based on ‘Pulverised Coal’, ‘Natural Gas Combined Cycle’, and ‘Integrated (coal) Gasification Combined Cycle’ power stations. Chemical and physical CO2 absorption capture techniques are employed with realistic transport possibilities to ‘Enhanced Oil Recovery’ sites or depleted gas fields in the North Sea. The selected options are quantitatively assessed against well-established economic and energy-related criteria. Results show that CO2 capture can reduce emissions by over 90%. However, this will reduce the efficiency of the power plants concerned, incurring energy penalties between 14 and 30% compared to reference plants without capture. Costs of capture, transport and storage are concatenated to show that the whole CCS chain ‘cost of electricity’ (COE) rises by 27–142% depending on the option adopted. This is a significant cost increase, although calculations show that the average ‘cost of CO2 captured’ is £15/tCO2 in 2005 prices [the current base year for official UK producer price indices]. If potential governmental carbon penalties were introduced at this level, then the COE would equate to the same as the reference plant, and make CCS a viable option to help mitigate large-scale climate change.

Research highlights
► Potential routes for carbon capture and storage (CCS) from UK power plants are examined, including six indicative options.
► Chemical and physical CO2 absorption techniques were studied with realistic transport possibilities to North Sea EOR sites or depleted gas fields.
► CO2 capture is shown to reduce emissions by over 90%, although incurring energy penalties between 14 and 30% depending on the CCS chain.
► Whole CCS chain ‘cost of electricity’ is estimated to rise by 27–142%, depending on the option selected.
► The corresponding average ‘cost of CO2 captured’ is £15/tCO2.This will determine the viability of CCS with market carbon prices.