Rhode Island's Blount Boats has cut a deal to build two crew transfer vessels to support US offshore wind farm projects.

The shipyard will build the ships for Atlantic Wind Transfers based on UK-based Chartwell Marine's Chartwell 24 ship design, modified for operation in the US northeast. They will be delivered in 2020.

"As the offshore market grows, so too does the demand for American-made [crew transfer vessels]," said Blount president and finance chief Marcia Blount.

"Building vessels to Chartwell’s proven design enables us to couple European design expertise with American engineering and support the domestic supply chain as it goes from strength to strength."

Blount built the first US-flagged crew transfer vessel for Atlantic Wind Transfers in 2015. The ship, the Atlantic Pioneer, worked on the first US wind farm off Block Island, Rhode Island.

There are 15 active commercial leases for offshore wind projects, according to industry group American Wind Energy Association, with 11 projects set for completion by 2026.

Those projects, which include wind farms offshore Massachusetts and New York, require Jones Act-compliant ships, meaning the vessels need to be substantially built in the US, owned by US companies and crewed by American seafarers.

“Based on our knowledge of the conditions off the coast of New England, we made modifications to our design to ensure optimal performance," said Chartwell managing director Andy Page.

"Compliance with maritime regulations is only second to the safety of personnel, so we have ensured that Atlantic Wind Transfers and its clients will benefit from a vessel that ticks all of these boxes, while attaining the highest possible standards of safety and technical availability."