PNNL

Abstract

The most significant energy development of the past decade has been the wide deployment of hydraulic fracturing technologies that enable the production of previously uneconomic shale gas resources in North America1. If this advanced gas production technology were to be deployed globally, the energy market could see a large influx of economically competitive unconventional gas resources2. The climate implications of the abundant natural gas have been hotly debated. Some researchers have observed that abundant natural gas substituting for coal could reduce carbon dioxide (CO2) emissions3-6. Others have reported that non-CO2 greenhouse gas (GHG) emissions associated with shale gas production make its lifecycle emissions higher than those of coal7,8. The assessment of the full impact of abundant gas on climate change requires an integrated approach to the global energy-economy-climate systems, but the literature has been limited in either geographic scope9,10 or coverage of greenhouse gases2. Here we show that market-driven increases in global supplies of unconventional natural gas do not significantly reduce the trajectory of GHG emissions or climate forcing. Our results, based on simulations from five state-of-the-art integrated assessment models11 (IAMs) of energy-economy-climate systems independently forced by an abundant gas scenario, project large additional natural gas consumptions up to +170% by 2050. The impact on CO2 emissions, however, is found to be much smaller (from -2% to +11%), and a majority of the models reported a small increase in climate forcing (from -0.3% to +7%) associated with the increased use of abundant gas. Our results show that while market penetration of globally abundant gas may substantially change the future energy system, it is not necessarily an effective substitute for climate change mitigation policy9,10.