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How Dominion is building its offshore wind farm — including underwater cables and a giant crane

A monopile installed at the site of the Coastal Virginia Offshore Wind project, with one of Dominion Energy's pilot turbines in the background.
Photo by Katherine Hafner
A monopile installed at the site of the Coastal Virginia Offshore Wind project, with one of Dominion Energy's pilot turbines in the background.

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, which is 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 says 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.

WHRO toured some of the initial construction – out in the ocean but also back on land.

Dominion's pilot wind turbines, as seen June 2024.
Photo by Katherine Hafner
Dominion's pilot wind turbines, as seen June 2024.

Building the offshore wind farm

The process of building the Virginia Beach wind farm starts far away from Hampton Roads.

Parts for the wind turbines and their steel cylinder foundations come 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 massive 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 vessel works to install a wind turbine foundation at the site of the Coastal Virginia Offshore Wind project on June 17, 2024.
Photo by Katherine Hafner
The Orion vessel works to install a wind turbine foundation at the site of the Coastal Virginia Offshore Wind project on June 17, 2024.

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.

On Monday, 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 90-100 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 on top until later.

The commercial turbines will be about 800 feet tall – 200 feet taller than the two pilot turbines already out there. Dominion says that may make them visible on the horizon from the Oceanfront on clear days, particularly at higher elevations or at night due to warning lights on top of 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 sightings of dolphins and sea turtles.

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

Chris Nunn with Dominion Energy stands at the beach on the State Military Reservation in Virginia Beach, where underwater cables from the wind farm will make landfall.
Photo by Katherine Hafner
Chris Nunn with Dominion Energy stands at the beach on the State Military Reservation in Virginia Beach, where underwater cables from the wind farm will make landfall.

Construction on the wind farm isn’t limited to the open ocean.

The company has to get the energy generated from it back onshore. 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 – 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 large, thick pipes that will then run underground for about five miles to a station on Naval Air Station Oceana.

Construction in March at the State Military Reservation in Virginia Beach, where ocean export cables will transfer electricity from the wind farm.
Photo by Katherine Hafner
Construction in March at the State Military Reservation in Virginia Beach, where ocean export cables will transfer electricity from the wind farm.

The electricity then gets ferried through 14 miles of new overhead transmission lines 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.

Cables waiting to be installed at State Military Reservation in Virginia Beach in March.
Photo by Katherine Hafner
Cables waiting to be installed at State Military Reservation in Virginia Beach in March.

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