Alpine lake veteran ferry to recharge the battery
A historic Swiss passenger ferry built in 1933 and now on its third diesel engine has to be re-engineered again, but this time with batteries. Carrying up to 60 passengers, the ferry, the Heimat, operates year round, making up to 12 daily trips between Maur and Uster on Lake Greifensee near Zurich.
Its electrification is carried out by the Norwegian battery and electric transmission specialist ZEM (Zero Emissions Marine) in partnership with the Lake Lucerne shipyard Shiptech AG which carried out a feasibility study of the project by evaluating the proposals of several suppliers. .
Towing tests and dynamic power measurements of propulsion and hotel charges have given Shiptec AG the information necessary to assess the most suitable dimensions and location of the engine and batteries, the likely life and an estimate. probable investment and operating costs.
The results confirmed the viability of the conversion and the shipowner SSG gave the green light, ZEM, which is owned by Volvo Penta, being selected on the basis of its experience with these types of vessels.
To power its typical 20 kilometers of daily operation, ZEM and Shiptec will modernize the Heimat with a 99 kWh AKAZEM lithium-ion battery system. Already proven in a variety of small ships and ferries, this solution will provide more than enough power for a normal working day.
SGG and Shiptec needed robust components with a high level of safety integrity. “This fits perfectly with ZEM’s values and the design of our system,” said Sebastian Wang-Hansen, project manager at ZEM. “Together with Shiptec, we therefore suggested upgrading the Heimat with an AKAZEM 99 kWh lithium-ion battery system and a 40 kW electric propulsion motor from Danfoss Editron. Danfoss permanent magnet motor provides high torque and is therefore able to drive the driveshaft without the need for a gearbox. The result is a transmission that is lighter, more efficient and requires less maintenance.
The vessel has an empty weight of 10.2 tonnes and a carrying capacity of 60 people, including 20 passengers in its cabin. The required speed should be maintained at the same 15 km / h as before the conversion, and the emergency stop should not exceed three and a half vessel lengths of 14.9 meters. The system requires 84 kWh of energy per day, including a reserve of 10 kWh, this includes 14 round trips on the lake and back, two round trips from Maur to Greifensee and back, as well as an additional trip in the evening at a lower price. speed. The ship needs 1.6 kWh of electricity to travel one kilometer.
THREE BATTERY SOLUTION
Three batteries of 33 kWh each were selected, for a total capacity of 99 kWh. This requires recharging during the day. There is a good 30 minutes of recharging between the hourly round trips. With a charging power of 30 kW, an energy charge of 15 kWh or 15% SOC is possible.
“It would be possible to equip a system with two batteries of 33 kWh each. The choice of three batteries allows a higher level of redundancy because if one battery fails, it is still possible to continue driving with two batteries without any limitation. We also expect the batteries to have a longer lifespan and allow greater flexibility of use on ships. The three-battery variant appears to be an optimization between redundancy, cost and weight, ”said Martin Einsiedler of Shiptec.
“The MS Heimat already provided a relatively sustainable public transport solution by removing the need for people to drive all the way around, around the southern or northern edge of the lake to visit either city, ”said the former president of SGG, Dr Allen Fuchs, who is leading the project. “But once the project is completed, it will provide a quieter and more environmentally friendly solution in harmony with the Greifensee Nature Reserve, while preserving the exterior appearance of the boat as a historically relevant example of motorization in the region.”
The Heimat will be the first joint effort between ZEM and Shiptec, and the partners expect other projects to develop from this cooperation. The pollution of maritime traffic on many Alpine lakes in Switzerland, Germany and Austria is of growing concern.
“ZEM can bring its Nordic maritime expertise to solve these challenges, by making new and modern tourist vessels electric and converting the traditional ferries that make Swiss lakes so unique,” said Jan-Olaf Willums, Norwegian founder of ZEM , who grew up in Switzerland.