Asserting the climate benefits of the coal-to-gas shift across temporal and spatial scales

Abstract

Reducing CO2 emissions through a shift from coal to natural gas power plants is a key strategy to support pathways for climate stabilization. However, methane leakage in the natural gas supply chain and emissions of a variety of climate forcers call the net benefits of this transition into question. Here, we integrated a life cycle inventory model with multiple global and regional emission metrics and investigated the impacts of representative coal and gas power plants in China, Germany, India and the United States. We found that the coal-to-gas shift is consistent with climate stabilization objectives for the next 50–100 years. Our finding is robust under a range of leakage rates and uncertainties in emissions data and metrics. It becomes conditional to the leakage rate in some locations only if we employ a set of metrics that essentially focus on short-term effects. Our case for the coal-to-gas shift is stronger than previously found, reinforcing the support for coal phase-out. The benefits of using natural gas as a bridge fuel are often called into question. A coal-to-gas shift in China, Germany, India and the United States is broadly consistent with climate stabilization goals in the Paris Agreement, except when metrics emphasizing very short-term outcomes are used.