A trailblazer for shipping: In the future, a methanol-powered ship will be sailing the North Sea. The research cutter “Uthörn” will be the first German ocean-going vessel to use this environmentally and climate-friendly fuel instead of marine diesel or heavy oil. The methanol for the fuel is to be obtained without fossil fuels using renewable energies. This makes ship propulsion almost CO2-neutral.
The 30-meter-long research ship Uthörn of the Alfred Wegener Institute for Polar and Marine Research (AWI) has been sailing regularly with students of marine sciences in the North Sea since 1982. On the voyages, they learn how to handle the ship and research equipment safely. In addition, the ship regularly measures the physical, chemical and biological condition of the North Sea around Heligoland and thus provides valuable long-term data.
Methanol instead of marine diesel
After around 40 years, there will now be a successor for the Uthörn: The new, 35-meter-long research ship is currently being built at the Fassmer shipyard in Berne, Lower Saxony, and should be ready for use in October 2022. In addition to its more modern equipment, the main difference between the ship and the old Uthörn is its propulsion technology. Because it is the first German ocean-going ship to be equipped with a methanol drive. Methanol is a liquid and combustible alcohol that can be obtained from fossil fuels, from cellulose, biomass, waste or directly from carbon dioxide.
When methanol is burned in engines, only the carbon dioxide is released that was previously bound from the starting product or the air in the methanol. Theoretically, the methanol drive can therefore be CO2-neutral – provided it is not generated from fossil fuels. In addition, less fine dust or other air pollutants are released than with marine diesel or heavy fuel oil. So far, methanol as a fuel in shipping has been a new and so far hardly tested concept. Nevertheless, there are successful role models. In a pilot project, the Swedish Maritime and Inland Navigation Authority has equipped an existing pilot transfer boat with a diesel engine that has been converted to burn methanol and has had positive experience.
Model for “greener” shipping
“The biggest advantage is the possibility of using ‘green’ methanol,” says Antje Boetius. “As soon as its production is coupled with renewable energies, the ship can be operated almost CO2-neutrally.” In order to secure supplies, a supply contract for green methanol is to be agreed. In the medium term, however, the goal is to produce the “green” methanol directly on site in Bremerhaven. A large competence center for hydrogen is currently being built there. In a model project, the renewable electricity from an eight-megawatt wind turbine is to be used to split water into hydrogen and oxygen by means of electrolysis. From this hydrogen and the carbon dioxide from a nearby sewage treatment plant, “green” methanol could then be synthesized in the next step.
The new drive brings even more environmental benefits. “Methanol dissolves very well in water; bacteria destroy it immediately so that in the event of an accident it does not pose a major environmental hazard,” explains Boetius. In addition, there is also a low level of soot pollution in the air. “When the alcohol methanol is burned, significantly fewer soot particles are released than with gasoline, diesel or heavy oil,” say Boetius colleagues Marius Hirsekorn and Michael Klages. “One challenge, however, is that the energy density of alcohol is only half as high as that of diesel. The new Uthörn therefore has significantly larger fuel tanks so that it can bunker enough methanol for a long range ”.
If the new construction of the research cutter proves itself, it could make an important contribution to sustainability. As the first German ocean-going vessel with a methanol drive, the Uthörn could become an important practical example and possibly make shipping significantly “greener” in the long term, hope Boetius and her colleagues.
Source: Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research