Life‐cycle performance of natural gas power plants with pre‐combustion CO2 capture

CO2 capture and storage involves technologies that separate, capture, and store CO2 from large facilities, such as fossil fuel power plants. Although it is a promising measure to meet environmental standards on carbon pollution, proposed technologies in power plants are energy demanding and decrease the energy generated per unit of input fuel when compared to business‐as‐usual scenarios. In this paper, we evaluate the environmental performance of two similarly structured combined‐cycle power plants with pre‐combustion capture. The first power plant performs methane steam reforming in an autothermal reformer, while the second plant uses a reactor that includes a hydrogen‐separating membrane. The two plants are compared both to one another and to a business‐as‐usual scenario using six environmental impact potentials (abiotic depletion, global warming, ozone layer depletion, photochemical oxidant formation, acidification, and eutrophication). The goal is to pinpoint environmental weaknesses and strengths of the two capture technologies. We find that the two plants result in similar impacts, decreasing the contribution to global warming of conventional operation but, at the same time, increasing other impacts, such as ozone layer depletion and photochemical oxidant formation. Additionally, the two capture plants result in higher cumulative non‐renewable and total energy demands, as well as in lower life‐cycle energy balances and efficiencies. The most direct measure to decrease the environmental impacts of the examined techniques would be to increase their efficiency, by decreasing the requirements of the processes in natural and energy resources.© 2014 Society of Chemical Industry and John Wiley & Sons, Ltd