Solving vertical clearance issue opens acreage for offshore operations

In early March, the New York City Economic Development Corporation announced an agreement with the Norwegian wind energy company Equinor, its partner, bp, and the Red Hook Container Terminal to reactivate the South Brooklyn Marine Terminal as a wind energy maritime shipping hub. The former container and breakbulk terminal, dormant since the 1980s, will support offshore wind projects awarded to Equinor by New York State.

Those consist of the two-phase, 80,000-acre Empire Wind, located 15 to 30 miles southeast of Long Island, with a capacity of two gigawatts, and the 128,000-acre Beacon Wind, 60 miles east of Montauk Point, which has the potential for another two gigawatts. Beacon Wind’s first phase, with a capacity of 1,230 megawatts, is currently under development.

Equinor and bp will be subleasing SBMT until 2054 for operations and maintenance activities and for an onshore substation. Equinor and bp also have a 10-year term for turbine staging and installation activities with an option to extend that term for up to six additional years.

Infrastructure upgrades at the 73-acre, New York City-owned SBMT are being funded by $287 million in public and private capital, including a $25 million grant from the federal Maritime Administration (MARAD) and $57 million from the city. The funding will add a barge berth and a heavy-lift crane pad on the western end of SBMT’s 35th Street Pier, increasing the terminal’s throughput capacity, as well as making other improvements to the 39th Street Pier.

“Engineering and design is starting in 2022 with construction anticipated to start in the second half of 2023,” an Equinor spokesperson told the AJOT. “We anticipate the South Brooklyn Marine Terminal will be ready to receive its first wind turbine generator components in the second half of 2025.”

The developments in Brooklyn invite comparison with the plans of the neighboring state of New Jersey to develop a wind port in the southern part of the state near the mouth of the Delaware River. Equinor’s competitor, the Danish company Ørsted, is developing the 1,100-megawatt Ocean Wind farm 15 miles off the southern New Jersey coast.

Transporting Offshore Wind Towers

Ørsted’s methodology calls for wind to be transported vertically on specialized vessels to installation sites, and the New Jersey location, south of any bridges that cross the Delaware River, was specifically chosen to avoid any problems with clearances. The Brooklyn site, by contrast, sits north of the Verrazzano-Narrows Bridge, which connects Brooklyn and Staten Island, creating a clearance problem, if towers are to be transported vertically.

A scholarly study cast doubt on the utility of using SBMT as an offshore wind marshaling port because of the clearance issue. An article in the journal Energy Policy noted that installation ports require “vertical clearance” in light of “the industry practice of assembling and commissioning the tower with its electrical systems in-port then shipping it out upright.”

That is Ørsted’s intention for its southern New Jersey operations—assembling the 500-foot towers and installing their blades in port, before craning them vertically on vessels and planting them in the seabed offshore. But the Energy Policy article makes clear that “South Brooklyn Marine Terminal…cannot build or ship out upright towers nor fully-assembled turbines…”

The Equinor spokesperson assured the AJOT that “there will be enough clearance to transport components, including towers, from the South Brooklyn Marine Terminal under the Verrazzano Bridge to the Empire Wind lease area.” That suggests that the towers are not going to be transported vertically.

A New York State document, “Assessment of Ports and Infrastructure,” part of its offshore wind master plan developed in 2017, suggested a solution when it concluded that “the vertical clearance for vessels to safely navigate below the Verrazzano Bridge “would require some components to be transported horizontally…” The documented also concluded that “SBMT may be used as a staging and installation facility if the offshore contractor were to adopt alternative installation strategies.”

A 2017 article in the Journal of Marine Science and Application describes a process by which a cargo barge would transport offshore wind turbine tower (OWT) assemblies “in the horizontal position to the site” at which point “a medium-size heavy lift vessel (HLV)” would “lift and upend the OWT assembly…” This installation method would eliminate the height constraints required for transporting towers vertically and obviate the need for huge heavy-lift vessels to be deployed in offshore wind installations. That would also reduce installation costs, an important factor, the article noted, in the high-cost, low-margin offshore wind industry.

Transporting offshore wind towers horizontally could have the effect of making more sites in the United States available as potential marshaling ports. The Energy Journal article concluded that the 150 gigawatts of state and federal offshore wind capacity planned by 2050 “yields more demand for marshaling area than is currently available or planned.” The country now suffers from a shortage of marshaling areas, the article noted.

The U.S. has just one offshore-wind marshaling port in operation, the New Bedford Marine Commerce Terminal, in Massachusetts, originally designed for the small Cape Wind project in Nantucket Sound. “Now,” the article noted, “New Bedford has been leased to help marshal the significantly larger Vineyard Wind 1 project,” an 84-turbine project offshore Massachusetts, but “due to limited port area, parts will have to be marshaled among three regional ports to accommodate the project’s size.

“The need to use three ports for a single project,” the study concluded, “already demonstrates a shortage of U.S. marshaling ports of sufficient area for modern turbine and project sizes.” It also increases Vineyard Wind installation costs, logistical challenges, and the time required, “while also complicating port availability for other projects set to be deployed within the same region and time period.”

At 73 acres, SBMT is over two and a half times the size of the 29-acre New Bedford. By solving the nagging clearance issue, the SBMT project points the way for the development of more acreage to satisfy the growing demand for offshore-wind marshaling ports, which, in the words of the Energy Journal article, is “the most challenging type necessary for large-scale deployment of OSW turbines.”