Posted on June 24, 2024
176 turbines will sit off the Virginia Beach Oceanfront.
This story was reported by WHRO News.
About 27 miles off the Virginia Beach Oceanfront, a pair of towering wind turbines come into view.
Dominion Energy’s two pilot turbines, each taller than the Washington Monument, went up in the summer of 2020 to help the company learn about how to install and maintain the structures.
For the past four years, they’ve been the only markers in a vast blue expanse that makes up Dominion’s federal lease area — the size of about 85,000 football fields. The company acquired the lease for $1.7 million through a federal auction more than a decade ago.
But soon, the two pilot turbines will simply be the entryway to a much bigger project. Dominion recently started building what will be the nation’s largest commercial offshore wind farm.
The $9.8-billion Coastal Virginia Offshore Wind project will include 176 turbines stretching as far as 42 miles off the Virginia Beach coast. The company said it’ll eventually produce about 2.6 gigawatts of electricity — enough to power up to 660,000 homes.
The utility started installing turbine foundations last month and plans to finish construction in late 2026.
Building the offshore wind farm
The process of building the Virginia Beach wind farm started far from Hampton Roads.
Parts for the turbines and their steel cylinder foundations came from countries including Denmark, Germany, Vietnam, Mexico and Portugal, according to Chris Nunn, engineering and construction director for the CVOW project.
“It’s truly a global type of fabrication process,” he said.
The materials are all staged at the Portsmouth Marine Terminal, including bright yellow “transition pieces” that connect the underwater monopile foundations to the turbines that are visible above.
Each monopile is designed for a very specific depth, based on its exact coordinates, with some stretching to 272 feet long to connect the turbine with the ocean floor, Nunn said.
Then comes the Orion, a 700-foot-long ship with a flat base and crane able to lift and lower each 1,500-ton monopile.
“The vessel itself is a very large crane, one of the largest cranes on any vessel in the world,” Nunn said.
The Orion can transport six foundations at a time from Portsmouth to the project site, said John Larson, Dominion’s director of public policy and economic development.
Recently, the ship was in the process of installing the project’s tenth monopile.
Each such installation takes about a day, Larson said. The Orion crew uses vibrations to initially drive the foundation into the seafloor.
“They put it exactly where it’s supposed to be positioned using GPS, then they start the installation with a soft start and vibrating it through sand,” he said.
Once the monopile reaches to a thicker layer of clay, a giant hammer drives it the rest of the way, about 90 to 100 feet into the seabed.
Right now, the installed foundations look like big cylindrical pipes poking a few feet out of the water. Turbines won’t be installed at the top until later.
The commercial turbines will be about 800 feet tall — 200 feet taller than the two pilot turbines already in place. Dominion said that could make them visible on the horizon from the Oceanfront on clear days, particularly at higher elevations or at night due to warning lights atop the turbines.
Nunn said installing foundations is the current priority, because Dominion can only do so during a limited window of the year — May through October, when endangered whales are least likely to pass through.
Environmental manager Mitchell Jabs said that’s one of several protective measures required by the company’s permitting.
“We know that pile driving, putting noise in the water has the potential to harass marine mammals,” she said. “Our mitigations in place are really designed to minimize the amount of noise that is propagated through the water, and also to ensure that all vessels are operating at a safe speed and minimizing any risk of a vessel strike.”
For example, construction workers use a “double bubble curtain,” sort of like a giant jacuzzi using bubbles to absorb sound.
There are also dedicated observers at the site to scout for animals passing through — and pause construction if so. Jabs said they delayed some initial piling, for example, due to dolphin and sea turtle sightings.
Dominion is currently facing a federal lawsuit from conservative groups that argue the Virginia Beach wind farm threatens endangered whales. Scientists have repeatedly said there is no evidence linking any whale deaths to the offshore-wind industry.
Dominion plans to have 90 turbine foundations installed by the end of October.
New onshore infrastructure
Construction on the wind farm isn’t limited to the open ocean.
The company has to get the energy generated from it back onshore — and that’s where underwater cables come in.
“The cables are how we get our power from the wind farm,” said Nunn, standing on the beach at the State Military Reservation in Virginia Beach.
This is where nine ocean export cables will make landfall, running under the seabed from three offshore substations at the project site. Cables run from each wind turbine to one of those substations.
Before laying all this infrastructure, though, Dominion has to clear debris from the ocean floor — everything from fishing nets to remnants of military activity.
“We did identify unexploded ordnances that have been here for decades, for training purposes and things of that nature,” Nunn said. “Our goal is to make the construction areas free and clear of any type of ordnance or debris that could cause harm to the cable.”
When the nine export cables hit the shore, they’ll be fed into pipes that then run underground for about five miles to a station on Naval Air Station Oceana.
The electricity then gets ferried through 14 miles of new overhead transmission line to the existing Fentress Substation in Chesapeake — and into the electric grid.
When construction is done, the area will be returned to a grassy field used as a rifle range. The only surface evidence of the landing at State Military Reservation will be some manhole covers.
Nunn said Dominion plans to finish most onshore construction by the end of next year.