Charting U.S. offshore wind
With offshore wind power getting a recent push from President Joe Biden, Dominion Energy�s Coastal Virginia Offshore Wind pilot project offers a possible navigational chart for offshore projects to come.
By Robin Brunet
It wouldn’t be an exaggeration to describe the Coastal Virginia Offshore Wind (CVOW)
pilot project as a landmark not only for Dominion Energy but also for the advancement of the nascent offshore wind power industry in the U.S.
Modest in size with two 6-megawatt turbines (enough energy to power 3,000 Virginia homes), the processes that brought the CVOW pilot project to life will facilitate future and much larger offshore wind projects.
“The lessons we learned through extensive collaboration with the Bureau of Ocean Energy Management (BOEM), Ørsted North America Offshore, the L. E. Myers Company, and many other organizations will serve us well as we move forward with a 2,600 MW commercial project, the largest announced offshore wind project in North America,” says Grant Hollett, Dominion’s Director of offshore wind.
Headquartered in Richmond, Virginia, Dominion powers the homes and businesses of over seven million customers in 15 states with electricity or natural gas, and one of its overarching goals is to achieve net zero carbon dioxide and methane emissions from its power generation and gas infrastructure operations by 2050.
The CVOW pilot and commercial projects commenced development in 2013, and Jeremy Slayton, Dominion’s media relations specialist, says of the long gestation period: “The pilot was our first project involving BOEM, and offshore wind was an entirely new proposition for them—they’re usually focused on oil and gas. So it was crucial to work with them and other organizations, including the Environmental Protection Agency and the U.S. Army Corps of Engineers, to ensure that the project would meet all regulatory requirements.”
The collaboration between BOEM and the other groups resulted in the ocean energy bureau determining the exact site for the pilot project: 27 miles off Virginia Beach where the water is about 80 feet deep. “The commercial site is adjacent to the pilot site and extends an additional 15 miles to the east, in deeper water,” Slayton says. The Virginia State Corporation Commission approved the CVOW pilot in November 2018.
While Dominion’s experience is largely in traditional forms of energy generation, its transition to a clean energy focus—and especially its work on the CVOW pilot—benefitted considerably from people such as Hollett, who is a veteran of the U.S. Navy, with degrees in mechanical engineering and business. He in turn credits Ørsted for tackling many of the daunting logistics of the project.
“They were the offshore engineering, procurement and construction lead, and we benefitted greatly from their expertise,” he says, adding that L. E. Myers performed the onshore construction work.
Equipment procurement and delivery was a task in itself. “The foundations were loaded in Rostock, Germany, components for the turbines such as the nacelle, tower, and blades, were loaded in Esbjerg, Denmark, and we created a staging area in Nova Scotia where many of these components were pre-assembled before being shipped south,” Slayton says.
He adds that normally under U.S. maritime law as interpreted by the Jones Act (which has no provisions for wind projects) a U.S.-flagged vessel is required to travel directly from U.S. port to U.S. port. “However, we required a jack-up vessel to not only transport the components from Nova Scotia but also install them off Virginia Beach, and because the vessel uses four legs that extend to the ocean floor to lift itself above the water and become a work platform, it is regarded as an U.S. port in this configuration.
“Additionally, there were no U.S.-flagged wind turbine installation vessels available, so we selected the Luxemburg-flagged Vole au Vent for the job, and needed to stage out of Canada to avoid any violations of the Jones Act.” Built in 2013, the Vole au Vent provided a huge work deck area of 3,400 square metres.
Pile driving two foundations for the two turbines was undertaken in the spring of 2020, and concurrent to the foundations being laid was the installation of a single export cable from the turbines to an electrical substation on shore.
“This is where the expertise of Ørsted and L.E. Myers really came into play,” Hollett says. “Extensive horizontal directional drilling was required, with L.E. Myers drilling down about 100 feet under the dunes and beach to a point approximately half-a-mile offshore. Ørsted received the drill bit at a near shore lift barge, and then a cable-laying vessel unspooled the cable from the shore out to the turbines. After that, the cable was buried under the sea floor to about six feet deep. The entire process took about a month.”
In conjunction with members of the International Brotherhood of Electrical Workers, L.E. Myers constructed the electrical interconnection facilities and the half-mile conduit that holds the final stretch of cable connecting the turbines to a company substation near State Military Reservation. “This job was completed earlier in 2020,” Hollett says, adding that the turbines were installed in June of that year.
Dominion Energy’s ultimate objective is to apply the permitting, design, installation, and operations experience gained from the Coastal Virginia Offshore Wind pilot project to Dominion’s 2.6-gigawatt commercial project, which will provide enough renewable electricity to power up to 660,000 homes. Construction on that project is scheduled to start in 2023.
Prior to the turbines being energized later that summer, then-Virginia governor Ralph Northam said that the CVOW pilot was the first offshore wind farm to be approved by BOEM and installed in federal waters, and second constructed in the U.S. “The project propels Virginia to national leadership in America's transition to clean energy,” he said. “It's also shaping a new industry that will bring thousands of new clean energy jobs to Virginia.”
The ultimate objective is to apply the permitting, design, installation, and operations experience gained from the CVOW pilot to Dominion’s 2.6-gigawatt commercial project, which will provide enough renewable electricity to power up to 660,000 homes.
Nearly 27.3 kilometers of new transmission lines and other onshore infrastructure have already been approved by the Virginia State Corporation Commission, and an updated Construction and Operations Plan will be submitted to BOEM in early 2023 (Dominion has to ensure that the project will not unreasonably interfere with other uses of the Outer Continental Shelf upon which the wind farm will be located, such as commercial and recreational fishing, commercial shipping lanes, and military training maneuvers). BOEM is planning to issue a draft Environmental Impact Statement later this year.
As was the case with the pilot, Siemens Gamesa Renewable Energy (SGRE) will supply the 176 turbines: each of these new SG 14-222 DD models will have a capacity of 14.7 MW and an 800-foot height from the water’s surface to the tip of a blade at its zenith (200 feet taller than the pilot’s turbines, Siemens Gamesa’s 6 MW SWT-6.0-154 turbines with 154-meter rotors), which will be deployed over an area equivalent in size to a staggering 85,000 football fields.
The energy from each turbine will be bundled together at three offshore substations; undersea cables will transmit it to the State Military Reservation (SMR) in Virginia Beach and continue underground through SMR to Naval Air Station Oceana.
From there, the energy will be transferred onto the broader electric grid by connecting to Dominion’s existing Fentress Substation in Chesapeake. Onshore construction is expected to commence in 2023; the offshore construction begins in 2024, and the project will be fully in service at the end of 2026.
Also echoing the CVOW pilot, the commercial project will be accompanied by a series of ‘firsts,’ including Dominion constructing its own $500 million wind turbine installation vessel, the Charybdis, to help meet maritime regulatory requirements, including the Jones Act, “and also to prepare for what we anticipate will be a host of other offshore projects in the future,” according to Slayton. Additionally, Siemens Gamesa has announced plans to establish a blade-finishing facility in Virginia’s port, which would create up to 310 jobs.
All of this is unfolding in the wake of U.S. President Joe Biden recently setting a goal to install 30 GW of offshore wind capacity nationwide by 2030. For its part, the American Clean Power Offshore Wind Economic Impact Assessment forecasts that 20,000 to 30,000 MW of offshore wind capacity will be operational by 2030, representing up to $57 billion of investment in the U.S. economy and an attempt to catch up to the much more established European offshore industry, which in 2021 alone installed 17.4 GW of wind power capacity (according to WindEurope).
It’s a lofty ambition, considering the only other offshore wind farm in operation besides Dominion’s pilot project is a 30 MW farm near Block Island, Rhode Island. Also, the only commercial-scale projects to have received full federal approval are the 800 MW Vineyard Wind project off Martha’s Vineyard, Massachusetts and the 132 MW South Fork Wind farm near Long Island, New York.
However, given the current political fervor for renewable energy, the chances of the U.S. improving its offshore wind capacity to a meaningful degree seem good. Meanwhile, the CVOW pilot is performing better than expected. “It’s very complementary to solar farms in that energy generation is at its peak at night and in the winter months,” Slayton says, adding that the two turbines are annually offsetting up to 25,000 tons of carbon dioxide emissions that would have been produced via traditional power generation.
Hollett adds that environmental monitoring—which includes bird flight observation and the study of marine growth around the turbines’ foundations —is ongoing. “We are monitoring bird activity at the pilot turbines and periodically conduct underwater surveys of fish, marine life and marine growth at the base of the turbines and along the underwater foundations. The marine environment is flourishing, and we are proud to share the research with the environmental community.
“All of this combined with our experience on the CVOW pilot will facilitate the development of the commercial component,” Hollett added. “All in all, it’s really exciting to be part of the birth of offshore wind energy in this country.”