Stockholm's transport authority has started using more of the city's waterways, providing to locals shorter and quicker routes to and from work. Yet, given that about the 80% of Stockholm's transport fleet of owned and leased vessels are far from achieving carbon neutrality, the city applauded the conversion of the M/S Rex to hybrid electric power.
The boat has room for up to 150 people and uses a Scania 13-litre diesel engine that is in line with IMO's Tier 3 emission standard.
[ To remind, NOx Tier III standards are in effect in ECAs from January 1st 2016. These limits apply to the North American and US Caribbean ECAs from 1 January 2016. However, MEPC 71 decided that from 1 January 2021, they will also apply to the Baltic Sea and the North Sea.]
Moreover, the boat includes an e-machine, meaning that it can approach the quayside silently. Its total propulsion power is 240 kW continuously or 290 kW for a short duration and it takes around 100 kW of power to run the boat at cruise speed, providing two hours' running time on pure electricity.
Fredrik Liw, who is the Technical Manager at Blidösundsbolaget commented that
There's still a lot of development and testing to do, but we could reduce CO2 emissions by up to 47% if quayside infrastructure is developed.
Concluding, the M/S Rex operates daily on a 75-minute route on Lake Mälaren, between Stockholm city centre and the island of Ekerö - known for two UNESCO World Heritage sites, including Drottningholm Castle, home to the Swedish Royal Family.