Response to Comment on 'Reassessing the Efficiency Penalty from Carbon Capture in Coal-Fired Power Plants'

摘要

While we appreciate the interest that Drs. Herzog, Rubin, and Rochelle have to respond to our paper, we categorically reject the assertions they make in their comment. We find it particularly noteworthy that while our colleagues find fault with the conclusions of the paper, they crucially do not identify errors in eq 1 from which the conclusions follow. Indeed eq 1 has been validated independently and serves as a natural extension from previous research in the literature. Their comment also fails to acknowledge that the scope of our paper was subcritical pulverized coal (PC) power plants with carbon capture and sequestration (CCS), particularly retrofits, such that they maintain the net electric output of an identical PC power plant without CCS. Our central approach, which is to compare power plants with and without CCS on the basis of equivalent net electric generation, follows from the standard practice of maintaining an equivalent functional unit when comparing technologies that could be treated as substitutes providing an identical service. Although our colleagues take issue with this approach, the very same approach was argued for elsewhere by Rubin et al. In fact, Rubin previously suggested that "the reference plant is assumed to be one that is identical or similar to the plant with CCS." Indeed eq 1 is a direct consequence of his correct and erstwhile guidance.