In July 2019 the Vilja became the first vessel to use Wärtsilä’s hybrid power module solution, the Wärtsilä HY.
Speaking during Tug Technology Week, organised by Riviera Maritime, Sundvall provided a summary of the first year of operations.
‘We actually got a better fuel economy than expected,’ said Sundvall.
Following Vilja’s hybrid configuration, a typical 90-minute mission would, in some cases, see the vessel consume around 40 litres of diesel fuel compared to around 200 litres for a fully mechanical setup, said Sundvall.
‘Of course, we have the electrical energy consumption on top of that but it’s still a lot of reduced emissions and also cost actually,’ said Sundvall.
‘We haven’t actually measured and gotten the figures yet…but in all I think we could reduce diesel consumption by half.’
Sundvall explained that all operations to and from missions were carried out exclusively in electrical mode – diesel consumption only occurs during tug missions – and that the port had been impressed by the performance of such configuration.
‘For the electrical mode, we get a slightly better range than expected,’ said Sundvall, adding, ‘we have done some missions, when assisting smaller vessels at least, fully electrically.’