Swedish tour operator Eco Sightseeing and electric marine specialists El & Marinteknik have revealed details of the retrofitting of a historic passenger boat with power supplied using Tesla second-life batteries writes Dag Pike.
Eco Sightseeing run a service in Stockholm Harbour under the name of Vasa Tours and run up to six trips every day taking tourists around the waterways of Stockholm Harbour. The company started this operation last year using an historic boat that was originally built in 1943 for the Royal Navy as a service boat. Constructed from wood the boat, called Sylvia took part in the D-Day landings in Normandy and she was acquired by Eco Sightseeing last year to operate on the sightseeing tours
The boat was originally powered by a Perkins four cylinder diesel engine but in keeping with the owner’s requirement and strong movements towards making Stockholm a greener city the decision was made to replace the diesel engine with electric propulsion which could be viable for the operating scenario of the boat on Stockholm’s waterways.
El & Marinteknik based in Stockholm were tasked with designing and developing the electric propulsion system and they selected an 85kW electric motor to replace the similar power from the Perkins diesel engine and using the same single shaft conventional propulsion system. To keep costs down the battery bank was sourced from batteries that were previously installed in Tesla electric cars which had had their service life cut short. These batteries were fully reconditioned and the batteries which total 190kWh, are housed in a bespoke aluminium casing installed in the bottom of the boat which provides a waterproof housing and also acts as a safety cell in case of battery malfunction.
The companies say that these batteries will allow up to 14 hours of cruising between charges which is adequate for daily operations with charging overnight. Eco Sightseeing founder Elias Nilsson started the company in 2019 and noted, “I wanted to accelerate the development of sustainable shipping in close urban waters. In Stockholm there has been talk of converting commercial vessels for many years. Talk and talk but nothing has happened and I believe now is the time for action.” The Sylvia can accommodate 49 passengers in a traditional varnished wooden interior.