Future natural gas consumption in the context of decarbonization - A meta-analysis of scenarios modeling the German energy system

Germany strives to reduce its greenhouse gas (GHG) emissions by at least 80% by 2050 compared to 1990 levels. In the underlying roadmap (Climate Action Plan 2050), natural gas is declared to be a bridge energy carrier into a carbon neutral era. But, since the roadmap only describes guiding principles and abstract transition paths, the concrete role of natural gas remains unclear. By analyzing 36 scenarios of eleven recent studies with respect to their GHG emissions, natural gas consumption, as well as their transition paths, we aim at understanding how decarbonization intensity and decarbonization strategies influence German future natural gas consumption. We find that as long as GHG reductions are less than 70% in comparison to 1990 levels natural gas consumption remains almost constant on average. However, German natural gas consumption in the scenarios varies by up to 500 TWh/a for identical GHG emission reductions. This divergence is driven by the decarbonization strategies applied. While some scenarios focus on switches from oil and coal to natural gas to mitigate GHG emissions, others favor a combination of energy efficiency and electrification of appliances currently running with natural gas. When GHG emission reductions are intensified, natural gas consumption declines considerably in almost all considered scenarios and the variances of projected natural gas consumptions narrow. In order to achieve those GHG emission levels, switches to natural gas are no longer sufficient. Hence, natural gas needs to be replaced. This is especially true when GHG emissions should be reduced by more than 80% compared to 1990 levels. Applied decarbonization strategies vary from extensive electrification of the end-use sectors, to a production of huge amounts of renewables (fuels and electricity), to an extensive utilization of synthetic fuels. All of these decarbonization methods reduce natural gas consumption. Only the scenario allowing for carbon capture and storage or usage in a large scale paves the way for constant natural gas consumption levels while still achieving high GHG abatement goals.