Climate and environmental effects of the manufacture of PtGLS products and technical measures for mitigation
Within the research project: Criteria for the sustainable provision and climate-friendly integration of electricity-based energy sources. Interim Report
Authors: Thomas Fröhlich, Axel Liebich, Sabrina Ludmann, Daniel Münter, Marian Rosental, Clemens Wingenbach
The aim of Work Package 3 in the research project “NEET – Criteria for the sustainable provision and climate-friendly integration of electricity-based renewable energy carriers” is to comprehensively assess the environmental impacts of synthetic energy carriers (PtGLS: Power to Gas, Liquids, Solids) and to identify options for action for the environmentally friendly design of these technologies. The focus is on analyzing how PtGLS products such as hydrogen, methane, methanol, ammonia, or liquid fuels can be integrated into a climate-neutral energy system in an ecologically sustainable way.
The chosen methodological approach is based on life cycle assessments (LCA) for 56 detailed modeled supply paths. These cover the entire process chain – from electricity supply via synthesis and derivatization to transport and reconversion. In addition, measures to reduce environmental impacts were derived and their mitigation potential analyzed in twelve target scenarios.
The results show that PtGLS products enable significant reductions in climate impact compared to fossil references in many cases – especially when using fully renewable electricity. For methanol, DME, ammonia, and Fischer-Tropsch fuels, greenhouse gas emissions can be reduced by up to 80%, while synthetic methane enables a reduction of around 60%. The choice of electricity source is crucial: wind power has the lowest climate impact, while the use of grid electricity can negate all climate benefits.
At the same time, in other environmental categories – such as acidification, eutrophication, particulate matter, resource consumption, and land use – there are in many cases higher impacts compared to fossil fuel-based products. This is due, among other things, to emissions from transport, infrastructure, chemical precursors, and high electricity and material requirements.
The study identifies specific mitigation measures for these environmental impacts, including the consistent use of renewable electricity, exhaust gas aftertreatment in ammonia processes, alternative membrane materials, and the use of seawater desalination to conserve freshwater resources. In addition, it highlights areas for action and conflicting goals that are important for future regulations and certification systems.
The study thus provides a sound basis for the ecological assessment and management of synthetic energy sources on the path to a climate-neutral energy supply.