Retrofitting the Regulated Power Plant: Optimizing Energy Allocation to Electricity Generation, Water Treatment, and Carbon Capture Processes at Coal-Fired Generating Facilities

Minimizing the human health and environmental impacts from electricity generation at existing coal-fired power plants (CFPPs) will require extensive plant retrofit, but the separations technologies for reducing CO 2 and wastewater emissions at CFPPs are energy intensive. This paper quantifies the electricity generation efficiency and revenue implications of allocating electricity, steam, or residual heat to these emission control processes under several different regulatory scenarios. We develop an energy balance model of the National Energy Technology Laboratory’s 550 MW CFPP without carbon capture (CC) and add models of five CC technologies (one electricity driven and four thermal processes) and five wastewater treatment (WT) technologies (one electricity driven and four thermal processes) to comply with the Clean Power Plan and Effluent Limitation Guidelines emissions regulations. Plant revenue is maximized by utilizing residual heat for WT or CC, but the optimal allocation of limited residual heat resources depends on the current regulatory environment. If both CC and zero liquid discharge WT regulatory standards are in place, the plant maximizes revenue by allocating residual heat and steam to amine-based CC and electricity to mechanical vapor recompression WT.