Millions of cars, trucks and vans travel on Europe’s roads every day – almost all of them still have petrol or diesel in their tanks. How can we make transport more climate-friendly in the future? This is exactly where a previously underestimated raw material could play a crucial role: residues from agriculture, forestry and organic waste. According to a new study, enough biogenic fuels can be produced from these to power all vehicles on Europe’s roads without fossil fuels.
The transport sector is one of the largest contributors to greenhouse gases. Although electromobility is becoming increasingly important worldwide and also in Europe, a large proportion of vehicles are still powered by combustion engines – and this could stay that way for a long time. In order to make transport climate-neutral, more sustainable fuel alternatives to fossil gasoline and diesel are needed.
Alternatives to fossil fuels
A research team led by Olaf Toedter from the Karlsruhe Institute of Technology (KIT) investigated what alternatives these could be. In their study, the researchers analyzed what amounts of biogenic raw materials – i.e. plant residues, wood residues or biowaste – are available in Europe, how they can be technically converted into renewable fuels and what fuel requirements road traffic will have in the future.
The researchers also looked at various manufacturing processes. One possibility is the so-called “Hydrotreated Vegetable Oil” process (HVO), in which oil-containing residues are processed to replace diesel. They also investigated methanol-based processes: Here, plant residues are first converted into a gas, which is then further processed to replace gasoline or diesel.
From residue to fuel
The result of the study is fundamentally positive: Europe could cover its entire road transport fuel needs from renewable sources by 2040 – and more than half by 2030. “In view of the current uncertainties on the international energy markets, this is good news. If we use residual and waste materials efficiently, we can make road transport less dependent on energy imports and at the same time reduce CO₂ emissions,” says Thomas Hirth, senior author of the study.
Large quantities of residual and waste materials could be used as raw materials for biogenic fuels, for example straw from agriculture, wood residues from forestry or biogenic waste. There are also catch crops and energy crops that do not compete with food production. This diversity ensures that the raw material base remains stable and does not depend on a single substance: “Many believe that used cooking oil is the central source of renewable fuels. In fact, it only makes up around one percent of the raw material portfolio,” says senior author Thomas Koch. “The really big potential lies in plant residues and wood fibers, for example. These substances are produced anyway – and can provide sufficient climate-friendly fuels.”
The HVO process can also be used in a variety of ways. “With these processes we can produce high-quality fuels from very different residues,” says Toedter’s colleague Nicolaus Dahmen. “This is important because Europe has a wide range of biomass. The technologies work even if the raw material mix changes.” While HVO is already available at the pump, fuels from other processes are still in development. They are already being manufactured at KIT and tested in cars. The tried and tested processes can also be used to produce large quantities of fuel. The study also shows that if additional hydrogen is added, the yield increases significantly.
Support from politics is needed
However, Toedter and his colleagues point out that their analysis is based on an optimistic scenario that is based on the goals of the Paris Climate Protection Agreement and whose prerequisites still have to be created politically and socially. According to the study, in order for renewable fuels to actually replace road transport, reliable political guidelines, investments and a rapid expansion of production capacities are needed. Imports could also play a role in the short term. By 2040 at the latest, Europe would be able to supply itself largely independently.
Source: Karlsruhe Institute of Technology (KIT); Specialist article: KITopen, 2026. doi: 10.5445/IR/1000191584