Designing the world’s first battery-methanol escort tug

Svitzer Balder, the world’s first battery-methanol escort tug, should be operating in the Port of Gothenburg, Sweden, from Q3 2026.

Owner Svitzer ordered this unique 35-m vessel from Turkish shipbuilder Uzmar with a TRAnsverse 3500 design that the Danish shipowner developed in conjunction with Canadian naval architectural firm Robert Allan Ltd (RAL).

Svitzer Balder has almost 6,000 kWh of battery capacity, two 350 ekW methanol generator sets, and one 1,960 ekW diesel genset that can also consume hydrotreated vegetable oil.

RAL project director Erik Johnston said fitting the batteries, three gensets, and fuel handling systems safely into the general arrangement of the escort tug was one of the biggest design challenges.

Another consideration was devising a method for safely venting methanol from storage tanks on the vessel, he said during a video interview at Riviera’s 28th ITS Convention in Gothenburg, on 19 May.

“We worked in close collaboration with Svitzer and Uzmar to find the optimal solution for integrating the two energy systems on board into one,” he said.

Another of the challenges was the weight of these battery modules and this impact of the tugboat’s stability and centre of gravity.

“We tried to get the batteries closer to midship so that they were not causing negative trim on the vessel,” said Mr Johnston.

Svitzer Balder will soon be on its way to Gothenburg to commence commercial operations for escorting tankers to the energy terminal in the port.