Natural gas has been consistently touted as a cleaner burning, more climate friendly alternative to other fossil fuels in a wide variety of applications. However, a new EPA study released on Tuesday calls into question the emissions reduction benefits of natural gas.
Previously, natural gas was though to have a significant edge in reduced emissions as compared to coal for electricity generation or gasoline for transportation. Studies noted that natural gas fired electricity generation produces significantly fewer sulfur dioxide, CO2 and particulate emissions as compared to coal. Similar results were found when analysing tailpipe emissions from natural gas vehicles (NGVs): lower carbon monoxide, CO2 and nitrogen oxide.
EPA’s new study expanded on the previous smokestack/tailpipe analysis to include the release of methane that occurs during natural gas extraction and transportation. According to the EPA, loose pipe fittings during the transport of natural gas release enough methane to be equivalent of 35 million cars on the road for one year.
EPA goes on to conclude that from this fact that the emissions benefits for natural gas power plants are on average only 40% cleaner than coal and some of more inefficient stock is only 25% cleaner. This study makes the political argument for using gas for electric generation and as a transportation fuel more difficult. As the emissions benefits of natural gas declines, the rationale for a wholesale switch becomes less compelling.
Prior to release of this study, utilities viewed natural gas as a ‘safe option’ for generation given the uncertainty surrounding climate rules in the future. These reduced emissions benefits leave utilities in a bind. If further studies validate the EPA’s conclusions, then natural gas’ value as a ‘bridge’ for electric generation declines significantly.
It is important to note that many factors are considered before a major commitment of company resources such as the choice of fuel type for generation. Consequently, the impact of this study on utilities’ decision making is yet to be seen and will likely be determined over the medium to long term.