Air quality and health benefits from potential coal power plant closures in Texas

摘要

As power production from renewable energy and natural gas grows, closures of some coal-fired power plants in Texas become increasingly likely. In this study, the potential effects of such closures on air quality and human health were analyzed by linking a regional photochemical model with a health impacts assessment tool. The impacts varied significantly across 13 of the state's largest coal-fired power plants, sometimes by more than an order of magnitude, even after normalizing by generation. While some power plants had negligible impacts on concentrations at important monitors, average impacts up to 0.5 parts per billion (ppb) and 0.2 μg/m~3 and maximum impacts up to 3.3 ppb and 0.9 μg/m~3 were seen for ozone and fine particulate matter (PM_(2.5)), respectively. Health impacts arose mostly fromPM_(2.5) and were an order of magnitude higher for plants that lack scrubbers for SO_2, with maximum impacts from a single power plant up to 178 deaths per year. Variations in impacts on ozone and PM_(2.5), and their associated health outcomes, were caused by sharply different NO_x and SO_2 emissions rates and spatial factors. Carbon dioxide emissions were relatively uniform, ranging from 1.00 to 1.26 short tons/MWh, and can be monetized based on a social cost of carbon. Combined monetized societal impacts from health impacts and carbon dioxide emissions ranged from $57/MWh to $143/MWh and exceeded wholesale electricity prices for all coal-fired power plants analyzed. This suggests that both air pollution and climate should be considered if externalities are used to inform decision making about power plant dispatch and retirement. Furthermore, while ozone receives the bulk of attention in Texas for air quality attainment, more health benefits can be realized through control of particulate matter via sulfur emissions.