Edison Chouest and Chartwell Marine to build US offshore wind’s first mini-CTV


US offshore vessel operator, builder and owner Edison Chouest Offshore (ECO) has launched construction of the US offshore wind industry’s first ever mini-crew transfer vessel (CTV), designed by Chartwell Marine (Chartwell), trusted UK pioneer of next-generation vessel design.

Set to begin operating in summer 2024 for the global and US offshore wind leader Ørsted and their US-based joint venture partner, Eversource Energy, the CTV will simultaneously accompany the launch of ECO Edison (pictured), the first ever American-built service operation vessel (SOV) announced in April this year. This so-called ‘daughter craft’ onboard the SOV can be deployed to efficiently manoeuvre crew across the Revolution Wind, South Fork Wind, and Sunrise Wind offshore wind farms in the Northeast US, under development by the joint venture.

Building commenced in July 2023 at Edison Chouest’s Louisiana shipyard, drawing components from US suppliers, and using Chartwell’s innovative design from its expanded range of offshore wind support catamarans — which has seen orders from across Europe, Asia, and the USA. ECO will manage the entire pipeline of construction and operation, supported by the incentives provided by the Inflation Reduction Act.

Chartwell’s design responds to the increasing demand in the US offshore wind market for low-emissions, cost-effective support vessels, with the catamaran’s optimised hull form offering efficient fuel use as well as stability and manoeuvrability in choppy waters. A first for this vessel type, the Volvo Penta IPS (integrated propulsion system) provides high power and performance as well as onboard comfort for operators. The system allows for a wide number of optional features and functions, featuring forward-facing, twin counter-rotating propellers with an individually steerable IPS under the hull.

The 12-metre mini-CTV has a capacity of up to 12 personnel and is designed to be conveniently deployed from ECO Edison during extended offshore stays, offering key staff comfortable and efficient access to turbines, vessels, and other critical project infrastructure.
Working closely with Ørsted throughout the design process, Chartwell conducted model testing in January 2023 to simulate and adapt to the specifications of the wind turbines that
will be installed at the Northeast US project sites. Considerations were made to facilitate Ørsted’s Get Up Safe system, which is a motion-compensated hoist solution that enables technicians to safely transfer between small moving vessels and offshore wind turbines without a ladder.

Andy Page, Managing Director of Chartwell, said: “This vessel is the small but essential chain connecting SOVs and turbines together. Engineers need to safely transition from larger vessels to turbines quickly and safely, and we set out to design an agile and streamlined vessel that has both bases covered.
“But it’s not a one-size-fits-all — turbines come in different configurations, with different requirements for effective crew transfer. That’s why we collaborated with Ørsted to thoroughly test and tweak our design to the joint venture portfolio’s particular needs. We’re grateful for their collaboration and honoured to have our design be the first out on US waters servicing the renewables industry, and with Edison Chouest at the helm, no less.”

Michael Braid, Vice President of Renewables at ECO, said: “ECO Edison needed to have the perfect partner on launch, and Chartwell has crafted her. As we look to further expand our fleet and activate it across a growing number of offshore wind projects, maintaining the efficiency of our transfers and our high level of technical availability will be key. Diversifying the range of vessels we use is one of the ways we can achieve that, but making sure they’re best-in-class is equally important.”

Mikkel Mæhlisen, Head of US Operations for Ørsted, said: “This vessel is yet another example that American offshore wind energy is providing economic opportunity and creating jobs across the US. Working with Chartwell and Edison Chouest to deliver an innovative design that accommodates Ørsted’s Get Up Safe system, the vessel represents the ingenuity of businesses in the maritime space to supply cutting-edge, purpose-built offshore wind vessels for safe and efficient operations offshore. This partnership is an innovative collaboration, one ready to serve the future growth of the American offshore wind industry.”

“We are proud to partner with Edison Chouest and Chartwell Marine to accelerate the transformation to a new clean energy future,” said Mike Ausere, Vice President of Business Development at Eversource Energy. “These vessels represent the incredible power of offshore wind to create American jobs in the industries of the future, deliver clean, renewable energy, and establish a US-based supply chain that will benefit workers and communities for generations yet to come.”