Destenie Nock, assistant professor of civil and environmental engineering and engineering and public policy at Carnegie Mellon University’s College of Engineering, co-authored a study that helps shed light on the future of gas power natural on the path to mitigating greenhouse gas (GHG) emissions. Taking a new international perspective, the team carried out a life cycle analysis for each of the 108 countries with gas-fired electricity in 2017, estimating total life cycle emissions for each. The work, published in Nature Climate Change, provides unprecedented insight and insight into GHG mitigation opportunities through national and international efforts.
As researchers, policy makers and industry leaders chart the course towards net zero GHG emissions, a growing number are looking to natural gas as a crucial bridge to the present. While energy systems are working toward a majority share of low-carbon energy sources, other efforts have sought a more immediate transition to natural gas and away from emissions-intensive fossil fuels (vs. natural gas), especially coal. Nock and the team faced many considerations when analyzing full life cycle emissions and the potential future impacts of massive investments in natural gas power as a transition fuel to net zero; these included transmission and distribution losses, methane leaks and a changing energy system.
Emissions from natural gas-fired electricity are generated long before the fuel reaches the power plant. In addition to the significant GHG emissions generated during its global transport, natural gas also generates methane at every stage of its journey, from extraction to exploitation and delivery as electricity. Methane is a significantly more potent GHG than carbon dioxide, which has increasingly raised questions about the effectiveness of natural gas in helping to reduce emissions over the long term. The authors also note the risk of overinvestment in fossil fuels and the possibility of unintentionally locking in fossil fuels beyond their usefulness to reduce emissions. These calculations are complicated by transmission and distribution losses in the electricity sector, which require more energy to produce than to consume. Nock provided equations and analysis for transmission and distribution losses in this analysis.
Nock and his colleagues determined that the global average life-cycle GHG emissions from gas-fired electricity delivery is 10% of global energy-related emissions, resulting primarily from electricity generation, followed by methane cumulatively generated by the natural gas process. drawn energy production. They note, however, that only 19-26% of emissions could be avoided through measures to reduce methane emissions and address inefficiencies in transport and delivery infrastructure. The researchers conclude that a significant deployment of carbon capture and storage (CCS) technologies must be part of any viable way to use natural gas to serve as part of a transition to lower carbon emissions. Compared to the other options studied, CCS could provide an additional 45-52% reduction in lifetime emissions from natural gas-fired electricity generation. Together, these advances could represent a 70% or more reduction in GHG emissions from natural gas-fired electricity generation.
The team notes the unique opportunities afforded by analyzes like theirs, identifying drivers of emissions in the gas supply chain nationally and internationally. This data can help decision-makers identify the best tools available to reduce GHG emissions in their region. They also highlight the importance of international efforts to reduce emissions, and in particular highlight the role that many international actors play at different stages of the gas supply chain – and the role that these actors can also play in leveraging leverage these interactions to support global decarbonization. With growing efforts and agreement at national and international levels in favor of cooperative decarbonization, the analysis and recommendations, according to its authors, represent “the first global study that delineates the emissions challenges and mitigation opportunities associated with the use of gas as a transient source of electricity generation.”