Classification service provider American Bureau of Shipping (ABS) has concluded a design review of the front end engineering and design (FEED) documentation of the US-based University of Maine’s (UMaine) new floating offshore wind turbine (FOWT) concept VolturnUS.

Developed by a team of UMaine’s Advanced Structures and Composites Centre, VolturnUS is based on a concrete, four-column, semi-submersible hull.

Completion of the review demonstrated the feasibility of the patented concept for use in offshore wind facilities. It also verified VolturnUS’ compliance with the ABS 'Guide for Building and Classing Floating Offshore Wind Turbine Installations'. 

As part of the review, ABS carried out an independent analysis of the hull and tower structures, as well as aeroelastic / hydrodynamic loads, safety, stability, electrical systems, equipment, and station design.

"We expect the VolturnUS hull concept to continue to attract private investment from the US and around the world."

UMaine director and principal investigator Dr Habib Dagher said: “After ten years of development, this is a major milestone for our programme, and we expect the VolturnUS hull concept to continue to attract private investment from the US and around the world.

“Nearly 70% of the US offshore wind resources can be captured using the UMaine VolturnUS technology, and we are looking forward to working with offshore wind developers across the US.”

In 2013, the UMaine team successfully tested the feasibility of the VolturnUS concept by developing a 1:8 scale model and deploying it offshore Maine, the northernmost state in the New England region of the US.

Under an ongoing pilot project, the team has developed two full-scale semi-submersibles, each with a 6MW turbine that is designed to be operational for 20 years. Both the units will be linked to the Maine power grid by subsea cables.

The US Department of Energy’s 12MW New England Aqua Ventus I offshore wind project is also expecting to use the semi-submersibles.

Image: Rendering of UMaine’s VolturnUS floating offshore wind turbine concept. Photo: courtesy of ABS.