While this wind farm is far north of Virginia Coastal waters, the danger it poses to migratory species such as whales and birds is still important to our state. The benefits are marginal, but the effects are substantial.
NOAA Fisheries has received a request from Revolution Wind, LLC, a 50/50 joint venture between Ørsted North America, Inc. and Eversource Investment, LLC, for Incidental Take Regulations (ITR) and an associated Letter of Authorization (LOA). The requested regulations would govern the authorization of take, by Level A harassment and/or Level B harassment, of small numbers of marine mammals over the course of 5 years (2023-2028) incidental to construction of the Revolution Wind Offshore Wind Farm Project offshore of Rhode Island in a designated lease area on the Outer Continental Shelf (OCS-A-0486), within the Rhode Island Massachusetts Wind Energy Area. Project activities likely to result in incidental take include pile driving (impact and vibratory), potential unexploded ordnance detonation, and vessel-based site assessment surveys using high resolution geophysical equipment.
NOAA Fisheries requests comments on its proposed rule. We will consider public comments prior to making any final decision on the promulgation of the requested ITR and issuance of the LOA; agency responses to public comments will be summarized in the final notice of our decision. The proposed regulations would be effective October 5, 2023 – October 4, 2028.
Paul Plante says
How Do Wind Turbines Survive Severe Storms?
JUNE 20, 2017
Office of Energy Efficiency & Renewable Energy
June starts hurricane season, an unsettling time for some people living near our nation’s shorelines.
For the next 6 months, communities will be on watch for severe storms and high winds that could potentially knock out power or damage homes and businesses.
Strong winds also put America’s growing fleet of wind turbines to the test.
Wind power recently surpassed 82,000 megawatts of total installed capacity, making it the nation’s number one source of renewable generation capacity.
You would think that during hurricane season, more wind means more energy, right?
It only works that way up to a point.
Wind turbines need to protect themselves just as communities do during tropical storms and hurricanes.
To understand what happens, let’s first discuss a wind turbine’s power curve.
The Power Curve
The diagram below shows the power output of a turbine against steady wind speeds.
The cut-in speed (typically between 6 and 9 mph) is when the blades start rotating and generating power.
As wind speeds increase, more electricity is generated until it reaches a limit, known as the rated speed.
This is the point that the turbine produces its maximum, or rated power.
As the wind speed continues to increase, the power generated by the turbine remains constant until it eventually hits a cut-out speed (varies by turbine) and shuts down to prevent unnecessary strain on the rotor.
Here’s how it works.
Measuring wind speed
Every wind turbine has an anemometer that measures wind speed and a wind vane to keep track of the wind’s direction.
When the anemometer registers wind speeds higher than 55 mph (cut-out speed varies by turbine), it triggers the wind turbine to automatically shut off.
Feathering the blades
When wind speeds surpass a modern utility-scale turbine’s rated wind speed, the blades begin to feather, or point into the wind to reduce their surface area.
In some instances, although not common, the blades can even be locked down to ride out severe gusts.
Despite this shut off, the yaw drive, located in the wind turbine’s nacelle, continuously points the rotor into the wind, even as weather patterns shift as they pass through.
Monitor and resume
Once the anemometer measures speeds at or below the turbine’s cut-out speed (in this case 55 mph), the blades unfeather and resume normal operation, providing renewable energy back to the grid.
Block Island’s First Test
This shut down process was on full display at Rhode Island’s Block Island Wind Farm—America’s first offshore wind farm—when winter storm Stella rolled through in March.
All five turbines were operating at full capacity (30 megawatts), except for a brief window of several hours when wind speeds exceeded 55 mph.
Although this was not a hurricane, it does demonstrate the shutdown process.
The wind farm sustained wind speeds higher than 70 mph during the automatic shutdown and successfully powered back up to serve Block Island after the winds diminished.
Paul Plante says
What a herky-jerky power grid Joe Biden is going to saddle us with, with his “green dream,” which is going to give us the type of undependable power grid, sometimes on, sometimes not, that one would expect to find in a third-world country like Haiti or Iraq:
Why do the turbines not spin at times?
The most common reason that turbines stop spinning is because the wind is not blowing fast enough.
Most wind turbines need a sustained wind speed of 9 MPH or higher to operate.
Paul Plante says
And WHOOPSIE-DOODLE big time here, Joe “THE GREEN DREAMER” Biden who wants to turn America, the America we who aren’t Democrats infatuated with Joe Biden know and love because things actually worked here before Joe Biden and his “GREEN DREAM” came along to make us equal to Somalia and Haiti because it’s the right thing to do!
Joe wants to gift us with the same type of unreliable and undependable power grid, never knowing when it will be on, or never knowing when a brown-out is going to occur to burn out your refrigerator motor, that is the hallmark or third-world countries like California, Haiti, Iraq and Somalia:
The Providence Journal
“Block Island offshore wind farm still down for maintenance and safety inspections”
14 August 2021
PROVIDENCE — For the better part of two months now, four of the five wind turbines at America’s first offshore wind farm haven’t been spinning.
Ørsted, the Danish offshore wind developer, shut down the turbines off Block Island in June for routine maintenance but also to carry out inspections after problems arose in Europe with the same model of turbine manufactured by General Electric.
Workers at the Merkur wind farm in the German North Sea found signs of stress fatigue on the support structures of the “helihoist” platforms on some of the project’s GE Haliade turbines.
Power generation at the 396-megawatt array was temporarily halted to come up with a solution to the problem, but the wind farm has since come back online.
Legislation proposed in the General Assembly would require Rhode Island to get all of its electricity from renewable sources, such as offshore wind, by 2030.
In June, Ørsted said it had put the five-year-old Block Island Wind Farm “on pause as a precautionary safety measure” to see if similar problems had arisen with the platforms at the top of the turbines that equipment and workers can be lowered onto from helicopters.
“We are working closely with the supplier on a solution that will allow us to safely restart generation as soon as possible,” Mikkel Mæhlisen, head of North America operations at Ørsted, said in an email at the time.
Ørsted said this week that workers from GE found “stress lines” in the Haliade turbines but that a risk assessment found that they are structurally sound.
Repairs and maintenance are expected to be completed in the coming weeks.
When the 6-megawatt turbines were installed in 2016, they were considered state of the art.
But the industry has advanced quickly in a short time, and developers are now investing in turbines of twice the power capacity and more.
Vineyard Wind, the first large offshore wind project to win federal approval, plans to use GE’s latest Haliade model, which has a 13-megawatt capacity, for its wind farm in the waters between Block Island and Martha’s Vineyard.
‘How can they make any money when the turbines are never running?’
The standstill at the Block Island Wind Farm hasn’t gone unnoticed by islanders and fishermen who frequent the waters around the turbines.
Richard Hittinger, first vice president of the Rhode Island Saltwater Anglers Association, said that for much of the summer he’s seen either one turbine turning or none.
He recently saw crews cleaning stains off the turbines and doing work on the blade tips.
“Guys on my boat have been commenting all summer ‘How can they make any money when the turbines are never running?’” he said in an email.
Ørsted said the cleaning witnessed by Hittinger is part of the regular maintenance of the turbines.
The company said that summer is the best time for such work.
That’s because the winds aren’t as strong or as steady in the warmer months, so it’s easier and safer for crews.
It also means that Ørsted isn’t losing as much money as it would if the wind farm had to halt operations in the winter, when generation typically goes up.
Compounded by ongoing problems with underwater cable
But the timing of the problem isn’t so good for the wind farm, because it comes amid ongoing difficulties with the underwater electric cable that takes power from the 30-megawatt project across Block Island Sound to the mainland electric grid.
While there have been no problems with the cable’s landing point on the mainland, in Narragansett, where a horizontal directional drill was used to bury it in a deep trench, it’s been a different story on Block Island, where a jet plow was employed at lower cost.
Because the shoreline off the island proved to be rockier than expected, the cable was buried at shallower depths than planned.
Waves soon started uncovering portions of it, and the problem grew worse over time.
Last year, in response to complaints from Block Island beachgoers and concerns from state coastal regulators, both Ørsted and National Grid decided to rebury the affected portions.
Although Ørsted was able to complete its share of the work without a hitch, National Grid had to suspend its part after discovering sand, mud and other material blocking a conduit pipe it installed under the seabed.
Will turbine repairs affect electric bills or power supply?
Work is set to resume in the fall, but it’s unclear how the difficulties will affect the $31-million cost of the replacement project and whether Rhode Island electric ratepayers will be on the hook if there’s an increase.
The surcharge that National Grid customers already pay for the cable has been the source of recent controversy.
The chairman of the state Public Utilities Commission has excoriated the company for a fee that he has described as wildly inflated and unjustified.
National Grid is in the midst of determining a new rate structure.
Despite the continuing issues, the cable is still in full operation, so Block Island’s power supply hasn’t been interrupted by the temporary shutdown of the wind farm.
And in another piece of good news, Rhode Island ratepayers aren’t on the hook for the repairs to the wind turbines.
Unlike National Grid, Ørsted, as stipulated by the long-term power sale contract approved by state regulators, cannot pass on any unforeseen costs to electric customers.