Probable cause of Vineyard Wind blade break identified

Editor's note: Vineyard Wind has since responded to claims that pieces of the offshore wind turbine blade washed up on Barnstable beaches. Here is the company's response.

A manufacturing problem appears to be the reason for the catastrophic break of a turbine blade in the Vineyard Wind offshore project that caused the giant blade to fold over and pieces to break off into the ocean, according to an executive with the blade's manufacturing company, GE Vernova.

During a quarterly earnings webcast Wednesday morning, GE Vernova CEO Scott Strazik brought up the July 13 incident south of the Islands. While the company has yet to finalize its root cause analysis, he reported that the investigation so far "indicates that the affected blade experienced a manufacturing deviation."

He stressed that analysts have found no indications of an engineering design flaw in the blade. There are also no indications that the blade's failure was similar to one experienced in May at the Dogger Bank A offshore wind farm in the North Sea off the coast of Yorkshire, England, which was "caused by an installation error out at sea," he reported.

Offshore turbine with a broken blade at Vineyard Wind 1, about 15 miles south of Martha's Vineyard, earlier this week. Pieces of fiberglass and foam have washed up on Nantucket, Tuckernuck and Muskeget islands beaches. Vineyard Wind officials have since said more of the blade has fallen.

Manufacturing problem missed at factory

Strazik elaborated that a "material deviation" was identified at GE Vernova's blade manufacturing factory in Gaspe, Canada that "through the inspection or quality assurance process we should have identified."

"Because of that, we're going to use our existing data and reinspect all of the blades that we have made for offshore wind," he said.

About 150 blades have been produced at the factory, according to Strazik. He did not say how many of those were created for the Vineyard Wind 1 project, a joint venture of Avangrid and Copenhagen Infrastructure Partners that's touted as the nation's first commercial-scale offshore wind farm. The 806-megawatt project will eventually have 62 turbines in operation 

"We are working with urgency to scrutinize our operations across offshore wind," Strazik said during the conference call. "Haste matters here, but we're going to be thorough instead of rushed."

He said "non-destructive testing" will be used to scrutinize the blades.

"Think ultrasound, think a radiologist, but for a blade, to identify deviations," he explained. "We are going to go and do this on every blade. A prudent, thorough process."

No timeline given

Strazik stopped short of giving a timeline for the investigation, saying only "we have work to do, but I have a high degree of confidence that we can do this."

Safety, he said, "always is the top priority," and the company is "working with our customer and the appropriate agencies to determine the root cause and then implement corrective actions and a restart plan."

Vineyard Wind spokesperson Craig Gilvarg on Wednesday said by email that the company has been receiving updates from GE Vernova, which also handles the blade installations, on the ongoing investigation into the blade incident, including its preliminary analysis of what happened. The blade was on a turbine that was still undergoing commissioning and had not yet been turned over to Vineyard Wind's control.

"As GE Vernova continues the investigation into the root cause of the damage to its blade, Vineyard Wind 1 remains focused on coordinating with the Bureau of Safety and Environmental Enforcement, assisting in the recovery of debris, and prioritizing the safety of personnel, local communities, and the environment," Gilvarg noted.

Operations at a standstill

Since the Vineyard Wind turbine blade began breaking apart, all operations have been at a standstill. Vineyard Wind CEO Klaus Moeller acknowledged the incident as "a very serious situation" and said the company immediately shut down operations. This was followed up by a formal suspension order from the federal Bureau of Safety and Environmental Enforcement calling for Vineyard Wind "to cease power production from all its wind turbine generators until it can be determined whether the blade failure affects any other VW turbines."

The agency's decision shuts down all power production in the lease area and suspends installation of new wind turbine generator construction until the order is lifted. The agency has also issued a preservation order "to safeguard any evidence that may be relevant to determining the cause of the incident."

At a meeting with the Nantucket Select Board last week, GE Vernova chief sustainability officer Roger Martella said a blade failure like the one in the Vineyard Wind project "is highly unusual and rare."

"This is not an acceptable outcome" and "not something we want to see repeated," he said.

Debris washes ashore

Since the nearly 351-foot blade started breaking apart, pieces of it have been washing ashore on Nantucket's south-facing beaches, as well as on Tuckernuck and Muskeget islands, and off Monomoy. Debris has included pieces of various sizes, consisting of fiberglass and foam.

Some residents of Barnstable also began reporting possible small fragments on Craigville Beach on Wednesday morning, Vineyard Wind has since conducted surveys on a number of Barnstable's south-facing beaches and found no debris related to the blade, according to the company. Spokesman Craig Gilvarg in a statement Thursday said no debris has been confirmed on the Cape at this time.

Environmental study: Primary risk is physical contact with fiberglass shards

An environmental analysis of the blade materials has also been undertaken by Arcadis, a Dutch design and engineering firm hired by GE Vernova to assess the mishap's effect on the environment.

According to initial analysis released Wednesday, Arcadis indicated "the current primary potential risk is injury to people who may physically contact the blade debris, (such as shards of fiberglass) on public beach and shoreline areas."

Other initial findings include:

• The blade materials and debris in their final product state are considered inert, non-soluble, stable, and non-toxic, akin to materials that can be found in textiles, boat construction and the aviation industry. This appliesto debris that has been observed on shore and which remains submerged at this time.
• The same final state materials do not require any specific environmental management and are considerednon-hazardous and classified for landfill disposal, when retired.
• The report notes there are no PFAS containing materials used in the manufacture of the blade itself or in thefoam, fiberglass, wood or coating. There are multiple small aerodynamic add-ons attached to the root end ofthe exterior of the blade (a common application in the industry) that contain PTFE, commonly referred to as Teflon, which is one of a broad set of chemicals categorized as PFAS and approved by the FDA for use in contact with food, potable water, and pharmaceutical products. The PFAS content in the aerodynamic add-ons account for 0.00005% of the total weight of the blade. At least 67 of 240 add-ons are visible as attachedto the blade, and
• additional add-ons may be present on parts of the blade that are not currently visible.
• To safeguard against contact with the debris, a dedicated hotline (833-609-5768) and online reporting tool are operational.

The Nantucket Select Board planned to discuss the environmental study during their meeting Wednesday night.

How to report debris

All found debris, no matter the size, should be reported to Vineyard Wind's hotline for collection, so the pieces can be analyzed and properly disposed of. Call 833-609-5768 or fill out the form at tinyurl.com/reportVWdebris