P.E.I. wind turbines at ‘high risk of imminent failure,’ consultant warned province in 2022 

Two blades broke off turbine T-09 at P.E.I.’s Hermanville wind farm during high winds in December. A year and a half earlier, a consultant had warned that some of the turbines were at ‘high risk of imminent failure’ and could pose a safety hazard. (Shane Hennessey/CBC)

A consultant hired in 2022 to assess production problems at a wind farm owned by the P.E.I. government found severe damage, with turbine units possibly constituting a safety hazard and turbine blades at “high risk of imminent failure.”

Last month, high winds ripped two 56-metre blades off one of the turbines at the facility in Hermanville, near the northeastern tip of Prince Edward Island. For comparison, the province’s tallest building is only 39 metres tall; it’s the 10-storey Holman Grand Hotel in Charlottetown.

A provincial spokesperson said the turbine was not operational at the time, and was scheduled for repairs in April 2024. The province also said it expected insurance would pay for the broken blades.

It was just the latest setback at a wind farm that has seen a steep decline in energy production and is now losing the P.E.I. government money.

The wind farm began operation in 2014, built at a taxpayer cost of $60 million.

Electricity generation had fallen to 10 per cent of design capacity by July 2023, with only four of 10 turbines operational and some of those running at reduced capacity because officials were concerned about damage.

In August, Energy Minister Steven Myers said the province would pay for repairs expected to cost $10 million, though it was planning to try to recoup those costs from Nordex, the company with the contract to maintain the turbines.

CBC News has obtained two consulting reports on Hermanville after filing an access to information request with the P.E.I. Energy Corporation, a provincial Crown agency.

A report delivered to the corporation in June 2022 from Montreal-based DNV Canada cited turbine blades with a “severe degree of damage or defect such that there is a high risk of imminent failure.”

DNV also concluded some of the turbines themselves had failed or missing components, representing “a critical impact to the operation of the turbine and/or a safety hazard.”

The consultant wrote that those turbines or components would have to be “taken out of service to prevent further damage. Immediate action to repair or replace is required before returning the component back to service.”

DNV catalogued multiple problems with the turbines, including cracked blades and bearings and damage to the systems meant to protect the turbines from lightning strikes.

Broken studs could lead to ‘catastrophic failure’

The company also observed broken blade studs, used to hold turbine blades in position, and warned that “in a worst-case scenario, should multiple blade studs fail nearly simultaneously, stud failures may progress and separation of the blade from the turbine could occur.”

DNV said there had been more than 200 blade stud failures reported at Hermanville as of June 2022.

During its inspection in April 2022, the company noted broken blade studs on three turbines at Hermanville, including T-09, the turbine that lost two blades in December 2023.

Another image of T-09 with one of its broken blades still dangling from the turbine tower. Each blade measures more than 56 metres in length – more than half the length of a CFL football field. (Shane Hennessey/CBC)

DNV said the number of broken blade bolts should normally be “near-zero,” and any breaks discovered should be replaced as soon as possible. “Otherwise the loads are transferred to adjacent bolts which can then in turn fail. A cascading effect of many broken bolts could lead to a catastrophic failure of the blade.”

The company suggested the province conduct ultrasonic testing to search for blades at risk of failure.

‘Potential root cause’ of damage

The province told CBC News that broken blade bolts were not responsible for the two blades severed in December, however.

In a statement, the province said T-09 was taken out of operation in August 2022 after a pitch ram failed. That’s the mechanism that allows the blade to be angled on its axis to adjust the amount of wind it catches.

“Early indications point to this as a potential root cause for the damage in December 2023, but further analysis will be required. A full root-cause analysis will be completed on T-09 in the coming weeks,” the province said in its statement.

“Once structural integrity has been determined, Nordex/Acciona will be providing options for how to proceed with this turbine.”

The province also noted that in the spring of 2022, damage to T-09 was ranked at a severity level of three out of four, which according to DNV “presents a potential impact to the operation of the turbine and/or safety” and requires that the damage be monitored until repairs can be scheduled “in [the] short term.”

Damage to other turbines had been flagged as more urgent, though, so those turbines were scheduled for earlier repairs, the province said.

No one from the P.E.I. Energy Corporation was made available in response to CBC’s request for an interview.

Technical issues with turbine model

When Hermanville opened in 2014, the province said it was the first commercial deployment in North America of the Acciona AW 116/3000 model of wind turbine.

The tower for each turbine stands 92 metres tall. Each blade is just over 56 metres long. (Shane Hennessey/CBC)

In its report from 2022, DNV noted that a number of technical issues had surfaced with that turbine design, particularly with earlier models, including broken blade studs, cracked blade bearings, and a shearing of the laminate covering from the turbine blade.

DNV said it does not consider the turbine to be a proven model in the North American region, though it said the design has “a significant track record.” At the time of its report, the consultant said the P.E.I. turbines should achieve the industry-standard operating life of 20 years.

CBC reached out to Nordex, the company that merged with Acciona in 2016, but did not receive a response.

Company expected province to pay for fixes

Another consultant hired by the province in 2023 described a plan to retrofit all the non-operational turbines at Hermanville that summer. The project seems to have been put on hold “when it became clear that [Nordex] was prepared to carry out these repairs at the expense of the [P.E.I. Energy] Corporation.”

The consultant, Frontier Power Systems, highlighted the urgency of the repairs required, also attributing many of the problems to “manufacturing flaws” and “major deficiencies” in the design and construction of the turbines themselves.

Dated February 28 of last year, Frontier’s report suggested necessary repairs could be completed over the summer, with the wind farm “largely renewed by the fall of 2023.”

But that timeline has now been pushed back by at least a year.

In the meantime, the P.E.I. Energy Corporation has seen its revenues drop to their lowest level since Hermanville came online in 2014, with annual electricity production at the site dropping to a third of what it was then. For the first time, the Hermanville wind farm operated at a financial loss in fiscal year 2022-23.

Warning of ‘legal quagmire’ over costs

Nordex is under contract to maintain the turbines until 2029, and that contract includes a stipulation that the company pay P.E.I. when production from the turbines drops.

But there are caps on those payments, which have almost been reached.

The Frontier report hinted at a legal battle between the provincial Crown corporation and Nordex over the cost of repairs that “will likely end in a legal quagmire that we cannot afford to have fully resolved before we take steps to return the non-operating turbines to service.”

The Frontier report also emphasized the importance of Hermanville, built to produce 30 megawatts of clean energy, as P.E.I. continues to electrify and pursue the most aggressive decarbonization timeline in Canada.

“The reliable operation of this wind plant is a critical part of the province’s electricity supply,” the report states. “With current generation limitations, ensuring this facility remains productive may be more important than simple financial optimization.”

Hermanville Operating Status – February 2023 (Frontier Power Systems)

Blair, is this correct?

T1 – Paused – Blade crack.

• Longitudinal Crack – Turbine Paused
• Blade Scheduled for repair Summer 2023

T2 – Operating – Curtailed to 1.5 MW with main bearing concerns.  Main bearing scheduled for replacement Summer 2023

T3 – Operating – No curtailment.

• Split Tip (repaired 2022) and another blade with trailing edge crack (currently in run until crack progresses to shear web), another blade was hit by lightning and replaced in 2021
• Scheduled inspection Summer 2023

T4 – Operating – Curtailed to 1.5 MW – Main bearing concerns

• Main bearing scheduled for replacement Summer 2023

T5 – Operating – Curtailed to 1.5 MW – Main bearing concerns

• 230126 – Blair reports turbine out of service due to blade cracks recently repaired.
• Main bearing scheduled for replacement Summer 2023

T6 – Paused – Failed Main Bearing

• Acciona plans to replace the main bearing at T6 in Q3-2022 postponed. Main bearing scheduled for refurbishment was beyond repair. Acciona is currently removing another in Texas which he hopes can be refurbished and the plan is to use this one at T6 and then start a cycle of remove and refurbish.
• RCA bearings?
• Main bearing scheduled for replacement Summer 2023

T7 – Paused – Blade Crack and Main Bearing

• Structural crack, which hasn’t yet reached the shear web – Turbine Paused
• Leading edge cracks needs to be repaired on the ground – Spare Blade is at T10
• Main bearing scheduled for replacement Summer 2023

T8 – Operating – No curtailment.

• Transverse crack, repaired in 2022, in run

T9 – Paused – Blade crack

• Two x Transverse crack, Blade C is a weird one because the drone photos show a crack beside the repair that was previously completed but Acciona inspected from inside and no damage was found. New drone inspections upcoming should help confirm this. Turbine paused because Blade A crack.
• Blade Scheduled for repair Summer 2023

T10 – Operating – Curtailed to 1.5 MW with main bearing concerns

• Blade replaced in 2021 due to Transverse Crack, I performed internal inspection of the blade that came down and it had already been repaired for Transverse Crack and the crack moved approximately 2 meters down the blade.
• Do you mean the crack propagated 2 meters toward the trailing edge or another crake started 2 meters further out on the blade?
• May be useful to get consultant or Nordex comment on this observation
• Main bearing scheduled for replacement Summer 2023