PITA Fiscal Year 2008 Projects - Product and Process Design and Optimization

Assessment Of Potential Heat Rate Improvement Opportunities As Part Of A Co2 Reduction Strategy For Coal-Fired Power Plants

It is highly likely that CO2 regulations will be passed sometime within the next few years which will require that U.S.coal-fired power plants operate with levels of CO2 emissions which are significantly less than is the case without CO2 controls. The challenges of reducing CO2 emissions will be the greatest for the owners of the existing fleet of coal-fired units, for these units were designed and built with no thought given to their being required to operate with carbon capture and sequestration. What might the owner of an existing plant do to reduce CO2 emissions? From what we know today, the main options are to convert the boiler to oxyfuel combustion or install one of several possible post-combustion CO2 capture technologies. Both approaches would be combined with geologic sequestration of the concentrated CO2.

The heat rate of a generating unit (heat rate is the reciprocal of thermal efficiency) will have a strong effect on the cost of carbon capture. More efficient units burn less fuel and generate less CO2 per net MWhr of output power, and this will result in lower costs for CO2 capture and sequestration,

Given the possible benefits of incorporating unit heat rate improvements into an overall strategy to minimize the costs of CO2 capture and sequestration, what are the potential heat rate reduction options, what is the largest practical reduction in net unit heat rate which can be achieved in a cost effective way, and how much would it cost? How would heat rate reductions translate into reductions in CO2 emissions when they are combined with oxy fired combustion or post combustion CO2 capture?

Using engineering and cost analyses of the potential heat rate improvement and CO2 capture technologies, this project will answer the questions: “What heat rate improvement strategies would it be cost effective to implement?” and “How can we use improvements in heat rate in combination with CO2 capture methods to minimize the cost of capturing CO2 from existing coal-fired units?”