09/07/2026

New Study on E-Fuels and Hydrogen: How the Industry Must Achieve Its Own Climate Goals

A comprehensive analysis assesses the environmental impacts of electricity-based renewable energy sources and identifies ways to further reduce greenhouse gas emissions

Renewable fuels derived from hydrogen and hydrocarbons (PtGLS: Power-to-Gas, -Liquid, -Solid) are considered key building blocks of a climate-neutral energy supply, especially for sectors that are difficult to electrify, such as international shipping, aviation, and the chemical industry. Sufficient quantities of additional renewable electricity are crucial for their production. A new study commissioned by the Federal Environment Agency now shows the environmental impacts arising along various production and transport chains of electricity-based renewable energy sources and identifies the measures needed to significantly reduce emissions.

As part of the NEET project (2023–2025), researchers from ifeu and Germanwatch analyzed the production, transportation, and conversion of electricity-based renewable energy sources. Based on this analysis, they were able to identify the key emission hotspots along the value chains and develop targeted mitigation measures. Following the refinement of the processes, the researchers recalculated and compared the environmental impacts for hydrogen and its derivatives.

The results show that greenhouse gas emissions can be reduced by up to 90 percent compared to fossil-fuel-based reference products through optimized processes. Nevertheless, even under optimal conditions, residual emissions of about 10 to 20 percent remain. These emissions arise in particular during the manufacture of photovoltaic systems, wind turbines, electrolysers, reactors, transportation equipment, and other infrastructure.

“Our findings make it clear that while hydrogen and e-fuels can make significant contributions to climate protection, these energy sources will only become fully climate-neutral when the industry that manufactures the necessary equipment and components also operates largely without fossil fuels,” said Thomas Fröhlich, project and department head for resources at the Heidelberg-based ifeu Institute.

Furthermore, the study highlights the need for action regarding the regulatory framework. For example, renewable energies have so far been classified as climate-neutral under European regulations, even though their production is also associated with emissions. In addition, existing regulations focus primarily on greenhouse gases, while other environmental impacts have not yet been adequately taken into account.

The results underscore that electricity-based renewable energy sources can make a decisive contribution to climate protection. For eine tatsächlich klimaneutrale Energieversorgung sind jedoch weitere technologische Fortschritte, ambitioniertere politische Rahmenbedingungen und die Defossilisierung der gesamten Industrie erforderlich.

Download Study „Kriterien für eine nachhaltige Bereitstellung und klimagerechte Integration von strombasierten erneuerbaren Energieträgern“ (in German)

Read the full press release (in German)

To the project NEET