Researchers: Differentiate in the transport transition

02.05.2025

Source: E & M powernews

A new monitoring report sheds light on the status and prospects of renewable energy sources in the transport sector - with a view to achieving climate neutrality by 2045.

In the current monitoring report "Renewable energies in transport", researchers analyze the progress of the energy transition in the transport sector. The German Biomass Research Center (DBFZ), the Technology and Promotion Center (TFZ) in Straubing, Bavaria, the Hamburg University of Technology (TUHH), the Paul Scherrer Institute (PSI) in Villigen, Switzerland, and the Fraunhofer Center for Chemical-Biotechnological Processes (CBP) in Leuna are involved. The focus is on both biomass and electricity-based fuels as well as renewable electricity - each in the context of a changing framework.

The report begins with an outlook on the future demand and availability of renewable energy sources. It presents the status quo of the transport infrastructure, the legal framework and the political goals and supplements these with an ecological and economic assessment. The publication builds on the previous DBFZ reports number 11 (2019) and number 44 (2022) and is published exclusively in digital form.

From the researchers' point of view, electrification is preferable due to the high energy efficiency benefits in all areas of transport. Nevertheless, it will still not be possible to fully electrify all transport segments by 2045. For these areas, the report specifically recommends the use of renewable pure fuels. However, the production of such fuels is challenging due to the limited availability of raw materials. According to the research institutes, new technologies and resources that have hardly been used to date are needed to meet future demand.

At the same time, electrification must also be driven forward in segments that are difficult to electrify, such as aviation and shipping. A long-term regulatory framework and investments in infrastructure, production capacities and research are required.

European solutions needed, says the study

According to the report, more than 50 million vehicles are currently in use in Germany, the majority of which are equipped with combustion engines for fossil fuels. This proportion is set to fall sharply by 2045. According to the analysis, cars, light commercial vehicles and motorcycles could be almost completely battery-electric. Electrification also appears realistic for trucks up to 18 tons and in regional heavy goods traffic.

In supra-regional transport, however, drives with hydrogen fuel cells, LNG or synthetic diesel fuels are being discussed. It remains to be seen which option will ultimately prevail - European solutions are needed, say the researchers.

The picture is similar for buses: electrification in local transport, renewable liquid fuels in long-distance transport. For mobile machines (NRMM), a differentiated approach is necessary depending on the performance requirements. While smaller machine applications can be electrified, the use of FT and HVO diesel, i.e. diesel from synthesis gas or vegetable oils, remains likely for more powerful equipment. In agriculture and forestry, regionally produced vegetable oil fuel is a suitable option.

According to the report, rail transport is already largely electrified. The remaining demand could be covered by battery or fuel cell vehicles and synthetic diesel.

Aviation and shipping, on the other hand, are considered to be particularly challenging. Only smaller units could be electrified, while the majority would continue to rely on renewable liquid fuels.

The authors of the report believe it is conceivable that the focus will shift in future from established options such as FAME (fatty acid methyl ester) or bioethanol to more flexible fuels such as HVO, FT diesel or synthetic kerosene, as these are also suitable for areas that are difficult to electrify.
Future options such as ammonia, dimethyl ether (DME) or oxymethylene ether (OME) are also being discussed - but are still at an early stage of development, according to the report.

The 205-page monitoring report "Renewable energies in transport" is available for download on the website of the German Biomass Research Center.

Author: Fritz Wilhelm