Green light for climate-friendly fuels in private shipping on Lake Constance

Cast off for the future

The "Climate-friendly Lake Constance" pilot project celebrated its successful launch at the Ultramarin Boatshow in Kressbronn on May 17 and 18, 2025. Under the motto "Cast off for the future", the project marks a milestone for sustainable mobility on the water. The aim is to gradually make the private boat fleets on Lake Constance climate-neutral - an important contribution to achieving the region's climate targets by 2040.

Funded by the Baden-Württemberg Ministry of Transport

The project is funded by the Baden-Württemberg Ministry of Transport, which is specifically supporting the ramp-up of alternative fuels in the leisure boating sector. It is part of the state's strategy for climate-neutral mobility and provides important impetus for other regions with high leisure boat traffic. The project is being scientifically supported by the Karlsruhe Institute of Technology (KIT). At the launch event, Ministerial Director Frieß (VM BW), Prof. Dr. Hirth (Vice President KIT) and Dr. Herrmann (VM BW) underlined the importance of the project for the entire Lake Constance region.

Innovative fuels for Lake Constance

The two climate-friendly fuels HVO100 and Nautic E10 are available at three filling stations on Lake Constance: Ultramarin in Kressbronn, Rudolf Bootservice in Constance (in preparation) and Bodenseenautic Busse in Wallhausen (in preparation).

Hydrotreated Vegetable Oil (HVO)

Nautic E10

Diesel fuel made from waste and residual materials such as used cooking oils or animal fats.
HVO 100 is completely renewable and reduces CO₂ emissions by up to 90 % over the entire life cycle.
Water protection class 1
Less particulate matter and pollutants
Further advantages: Smooth engine running, good storage stability, in use at Ultramarin for over two years without any problems.

Petrol with 10% bioethanol content, which enables CO₂ savings of around 8.5%.

E10 has been established at filling stations for 15 years.

fuel has been optimized for use in boats: A special additive prevents the storage of water and thus protects against corrosion, even during longer downtimes.

Over 90% of existing engines are suitable for use with E10.

Sustainability and transparency

The fuels used are certified and come from sustainable supply chains. With the help of the "Digital Fuel Twin" tool developed by Bosch, the CO₂ savings are precisely calculated for each refueling and shown directly on the receipt - a unique feature in Europe. This provides environmentally conscious boat owners with transparent proof of their contribution to climate protection.

In addition, this system can play a central role in the ramp-up of renewable fuels: Precise documentation means that CO₂ savings can be comprehensibly documented and used for statutory crediting models or funding mechanisms.

Scientific support and regional pioneering role

KIT is providing scientific support for the project and ensuring that the transition to the new fuels is smooth and safe. The experience gained from the pilot project will be incorporated into the further development of climate-neutral shipping on Lake Constance. The state government of Baden-Württemberg is thus setting a
strong signal for sustainable mobility and is taking on a pioneering role in climate-friendly shipping within the International Lake Constance Conference.

Easy transition for boat owners

For the owners of private boats, the pilot project means that they can now make an active contribution to environmental protection on Lake Constance without having to make any technical changes or change their behavior. The boat workshops are on hand to answer any questions.

Outlook

The pilot project is the starting signal for a climate-friendly future for shipping on Lake Constance. Further filling stations will follow, and an expansion to Switzerland and Austria is already being planned. With the "Climate-friendly Lake Constance" project, the region is becoming a role model for sustainable mobility on the water.
water - for a future worth living on Lake Constance.