BC Ferries has delayed the refit of its workhorse Spirit-class vessels by a year to accommodate plans to convert them to a dual-fuel system using liquefied natural gas.

The Spirit of British Columbia is to begin its refit in the fall of 2017, with the Spirit of Vancouver Island to follow in 2018. The fuel conversion will be included in the mid-life refits for vessels built in Victoria in the early 1990s for the Tsawwassen-Victoria route.

Seaspan's Vancouver Shipyards, Remontowa SA of Poland and Fincantieri of Italy have been short-listed for the refits, with the contract to be awarded by the end of 2015.

Remontowa SA is building three new intermediate-class ferries in Gdansk, Poland, with delivery of the first expected in August 2016 to replace the 50-year-old Queen of Burnaby on the Comox-Powell River run.

The second is scheduled to arrive in October 2016, replacing the 51-year-old Queen of Nanaimo on the Tsawwassen-Southern Gulf Islands run. The third is scheduled for service February 2017, for peak and shoulder season use on the Southern Gulf Islands route and as a refit relief vessel for others in the fleet.