Are wind turbines safe? N.Y. accident stirs debate

Source: By David Iaconangelo, E&E News reporter • Posted: Monday, January 6, 2020

The sudden collapse of a wind turbine in a densely populated New York City neighborhood has alarmed state and city officials, who are promising investigations and new legislation in response to the accident.

The turbine on the roof of a strip mall in the Bronx came apart amid high winds Monday, taking with it its foundational monopole tower.

The structures fell into the strip mall’s parking lot, flattening one car and damaging several others, according to the New York City Department of Buildings. No one was injured.

State legislators representing the area called on city building authorities to find out how — or if — the property owner had been permitted to put up the structure.

“There are many yet unanswered questions about the permission to build and the stability of a structure that was put up literally as residents of Co-Op City slept,” state Sen. Jamaal Bailey, a Democrat, said in a statement posted on Twitter.

Bailey said the Co-op City housing complex, whose grounds encompass the strip mall, was “no place for this type of structure.”

“We will be taking legislative steps in order to ensure that this doesn’t occur again,” he wrote, without elaborating.

A spokesperson for the Department of Buildings said officials had vacated three nearby businesses and issued two violations to the property’s owner as part of an ongoing investigation of the incident.

Attempts to reach the property’s owner, listed as Baychester Retail III LLC, were unsuccessful.

The site’s “vertical axis” turbine technology, a kind not widely deployed in the United States, uses blades that turn around a vertical rotor in a way that can resemble the mixer on a food processor.

Stacey Kerans, spokesperson for the American Wind Energy Association, referred questions to a smaller industry association for distributed wind, saying the vertical axis technology isn’t used to generate power at any utility-scale wind farms.

“The turbine that collapsed in the Bronx was from a distributed project, which features very different technology and siting practices than utility-scale turbines,” wrote Kerans in an email.

‘Extremely rare’

Energy experts and wind engineers say collapses like the one in New York are rare for large-scale wind, although the industry doesn’t publish comprehensive data. One Energy Department report from 2015 estimated that fewer than 40 “catastrophic wind turbine failures” had occurred on over 40,000 turbines in service the year before.

Paul Veers, chief engineer at the National Wind Technology Center, said that design standards for large turbines developed by the International Electrotechnical Commission in the 1980s had effectively minimized the number of accidents.

“These kinds of failures of the primary structure — the machine coming apart — they happen, but they’re extremely rare,” he said.

The configuration of the Bronx turbine looked unusual, he added. “I’d never seen a machine of that type deployed on a pole of that size before in my life.”

Anti-wind groups have seized on a smattering of studies and news reports of failures to suggest the risks associated with turbine failures are being overlooked.

One such study from researchers at Imperial College London, which appeared in the International Association for Fire Safety Science’s academic journal in 2014, found that turbine fires often didn’t become public knowledge through news reports or other sources, and concluded that fires occurred about once a month, globally. That study has been cited by opponents of one 350-megawatt wind farm slated for development by Avangrid Inc. in upstate New York.

The incident also may not help the optics of wind turbines at a time of recurring conflicts between residents and turbine developers in New York, which is planning one of the country’s fastest transitions to an entirely renewable grid.

In December, a state siting board found that a Houston-based wind developer did not have to abide by a local zoning law enacted at the tail end of a three-year regulatory process, calling the new rules “unreasonably burdensome.”

Officials in the rural town of Sanford, in upstate New York, had cited concerns about property values and aesthetics if the $200 million, 124-MW project went forward.

The siting board said the project, like other wind and solar installations, would be “vital” for New York’s progress toward its climate targets, which include 70% renewable electricity by 2030.

Veers, who helped design vertical-axis turbines while an engineer at Sandia National Laboratories, said the technology was still generally considered experimental, though it could prove easier to maintain than the traditional kind.

Offshore wind would likely be the biggest focus for a renewable build-out in New York, he said. “Whereas this machine in the Bronx might be delivering a few kilowatts, the offshore potential in New York is a few gigawatts. That’s the biggest opportunity in the near term,” said Veers.