The world’s second-largest ferry operator, Washington State Ferries, in the north-west of the United States has reportedly made the decision to transition its fleet of ferries from diesel to battery, according to Greentech Media.

Ian Sterling, public information officer for Washington State Ferries, told Greentech Media that the state-run agency will seek to electrify its entire fleet of ferries, starting with the most polluting vessels, three Jumbo Mark II ferries which together consume 5 million gallons of fuel a year.

The agency has also initiated a new-build program for electric ferries that will apparently see Olympic-class electric-diesel hybrids entering operation within three years.

According to Sterling, Washington State Ferries consumes fuel at a level similar to a “midsize airline” which makes it Washington State’s largest polluter.

The agency annually consumes nearly 20 million gallons of diesel across its fleet of 22 vessels.

However, in line with Washington State Governor Jay Inslee’s mandate to strive for zero emissions, it is now moving ahead with an electrification effort which will likely see Washington commuters riding some variation on an electric-powered ferry “in the next couple of years.”

Ian Sterling also made the case that the agency was not making the move “just because the governor said [to do] it” but that “This is a good idea because it quiets the boats [while] obviously removing tons of diesel fuel emissions.

But even if you’re not an environmentalist, this is a good idea for the taxpayer because we expect it to pay for itself relatively quickly, based on the price of fuel. It saves millions of dollars annually.”

The agency had apparently already investigated the possibility of using hybrid or liquid natural gas-powered vessels as far back as 2012, but the technology was not mature enough at the time.

However, even with this announcement, the electrification process will not necessarily be swift, given the difficulty inherent in installing necessary charging infrastructure and signing electricity supply agreements in some Washington State locations – especially considering the agency runs services across the majority of Puget Sound, which covers more than 1,000 square miles.

The electrification program will also necessitate a major quayside electrification effort, with the Seattle-Bainbridge Island and Mukilteo-Clinton routes expected to be the first routes with charging points at both ends.

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