Embarrassing blade failure and the struggle for answers at first offshore wind farm in US

Developers of the first commercial-scale offshore wind farm to be built in the United States are still struggling to find answers to why one of the project’s brand new GE Vernova turbine blades crumpled, causing debris to wash up on Nantucket beaches and bringing the pioneering project to an embarrassing halt.

In an update published over the weekend, developers of the 800MW Vineyard Wind project say initial assessments have found that a “manufacturing deviation” is the likely culprit – a fault they say “should have been identified through the quality assurance process at the blade manufacturing facility.”

The 62 turbine project – a joint venture between Avangrid, a member of the Iberdrola Group, and Copenhagen Infrastructure Partners – was expected to demonstrate the huge potential for offshore wind in the US.

However, damage to one of the massive 13MW Haliade-x wind turbines during testing in mid-July has brought the half-built project to a halt, including construction activities and operation of the turbines already fully installed.

The accident has provided significant ammunition to those already opposed to offshore wind farms and renewable energy and required the creation of a 500-metre safety exclusion zone around the turbine by the American Coast Guard.

After weeks spent picking up the pieces, quite literally, of the turbine failure, Vineyard Wind has now published an action plan to safely remove the remainder of the damaged blade and ensure there is not a repeat.

This has included the “controlled detachment” of the parts of the damaged blade that remained attached to the turbine, followed by “controlled cutting activities” on the offending turbine, further reducing the amount of the damaged blade still at risk of falling into the ocean.

The developers have revealed that they have been granted permission to resume some construction activities at the project, including the installation of turbine towers and nacelles, but further blade installations and power production from the installed turbines are both still on hold.

First power from Vineyard Wind was generated in January. Image Credit: Vineyard Wind

“The updated Suspension Order is the result of extensive consultation with the Federal Interagency and third-party experts to ensure these future steps uphold the highest safety and engineering standards,” an update from Vineyard Wind said on Tuesday.

“The Order follows thousands of hours devoted to the plan’s development, review, and testing, including evaluation against all other alternatives to arrive at the best, safest approach for a successful operation.”

Meanwhile, a Preliminary Root Cause Analysis of what went wrong with the GE Vernova wind turbine is being assessed independently by Gulf Wind Technology, a premier wind turbine engineering firm.

This analysis will include a review of thousands of ultrasound images per blade, preserved from the manufacturing process, to identify and address any further anomalies.

Further, advanced remote-controlled robots called “crawlers” are being inserted into the manufactured blades to allow for visual inspection, the action plan says. Each crawler is equipped with video camera to visually inspect critical areas of the blade with photos and video.

For GE Vernova’s part, the turbine manufacturer is said to be deploying a new algorithm, using existing sensors already in the blade, that will monitor blade health to avoid similar events. “The algorithm will provide advanced warnings or automatic, safe turbine shutdown when required,” the report says.

“From the start of this event, our response has been focused on the safety of everyone involved,” said Klaus S. Møller, Vineyard Wind CEO.

“As we move forward to this next phase and begin removing the remainder of the damaged blade, we will continue to safeguard the public and the environment through our robust land, air and sea debris recovery system.

“Vineyard Wind is a critically important project for the region’s energy future, and delivering this project safely is our highest priority.

“We believe we have the right plan in place to recover the rest of the blade, secure any debris offshore and onshore, and safely and responsibly resume the installation program so we can put this project back on track to deliver needed clean power to the New England region.”