Optimizing CO 2 avoided cost by means of repowering
Abstract
Repowering fossil fuel power plants by means of gas turbines has been traditionally considered to increase power output and reduce NOx and SO 2 emissions both at low cost and short outage periods. At present, reduction in CO 2 emissions represents an additional advantage of repowering due to partial fuel shift and overall efficiency increase. This is especially important in existing installations with a CO 2 reduction mandatory that should be carried out in a short time and in a cost-effective manner.
Feedwater and parallel repowering schemes have been analysed using thermodynamic, environmental and economic simulations. The objective is not only to evaluate the cost of electricity and the efficiency increase of the overall system, but calculate and minimize the cost of CO 2 avoided as a function of gas turbine power output. It seems that integration of larger gas turbines reduces the overall CO 2 emissions, but there is a compromise between CO 2 reduction due to fuel shift and a optimum integration of waste heat into the power plant to minimize the CO 2 avoided costs. Results highlight the repowering as a suitable technology to reduce 10-30% of CO 2 emissions in existing power plants with cost well below 20 €/tCO 2. It could help to control emissions up to the carbon capture technologies commercial development.- Publication:
-
Applied Energy
- Pub Date:
- 2009
- DOI:
- 10.1016/j.apenergy.2009.02.015
- Bibcode:
- 2009ApEn...86.2351E
- Keywords:
-
- Repowering;
- CO <SUB>2</SUB> emissions;
- Energy optimization;
- Energy integration