More than 4,000 gigawatts of estimated gross offshore wind potential lies off the U.S. coastline—that’s more than four times the current generation capacity of the United States. With the coastal and Great Lakes states consuming nearly 80% of our nation’s electricity, offshore wind can play a major role in supplying energy to regions where electricity demand is at a premium. Offshore wind in the United States is just starting to take firm hold on the East Coast with the installation of the Block Island Wind Farm in Rhode Island, but the U. S. Department of Energy’s (DOE’s) Offshore Wind Advanced Technology Demonstration Projects are not far behind. Fishermen’s Energy, in partnership with DOE, is looking to install turbines 3 miles off of Atlantic City, New Jersey, in water that is about 35 feet deep. These turbines, with a rotor diameter bigger than a football field, will be installed on “twisted jacket” foundations developed by Keystone Engineering. A twisted jacket foundation has a base set up in which the legs are angled around a central column, making it easier to manufacture and install.

Although the U.S. offshore wind industry could create thousands of manufacturing, construction, and supply chain jobs across the country and drive billions of dollars in local

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economic investments, one challenge with offshore wind is that technicians cannot just hop in a truck to go perform maintenance. Whether it is changing oil in a hydraulic system, performing regular visual inspections, or doing significant repairs on the turbine, technicians have to be able to access the turbine. After the boat ride out to the offshore wind turbine, an offshore worker has to account for the wind and the swell of the waves to make a perfectly timed step off the boat onto the access ladder. The access ladder is connected to one side of the foundation. In other countries with offshore wind plants, workers have to reach across a gap to grab onto the ladder hand rails, and step across that gap while the boat is still moving. U.S. regulations call for a narrower gap between the boat and the ladder, but stepping across a narrower gap can be more dangerous for the workers because of the unpredictable motion of the boat. So, with DOE funding, Fishermen’s Energy and Keystone Engineering went back to the drawing board and came up with an innovative and safer solution.

“Unlike traditional ladder access where the worker steps from the vessel forward across a gap to the ladder, our innovative ladder is rotated 90 degrees so that the vessel deck can be placed as close as possible to the ladder rail and allow the offshore worker to safely side step onto the ladder,” says Stan White, program director of Fishermen’s Energy. “If the offshore worker were to accidentally fall, the worker will not be pinned between the vessel and the ladder but, instead, the worker would fall in a clear space protected by the fender system.”

Fishermen’s and Keystone wanted to demonstrate the safety improvement of this new ladder. So with the support of DOE, they contracted Gulf Island Fabricators in Houma, Louisiana—the same fabrication yard that built the Block Island Wind Farm foundations—to build a full-scale mock-up of the new ladder for offshore technicians, engineers, and regulators to climb on and test out. They also built a full-scale mock-up of the conventional access ladder as a comparison. On August 13, representatives from the Bureau of Ocean Energy Management, Occupational Safety and Health Administration (OSHA), U.S. Coast Guard, American Bureau of Shipping, Siemens, and GE were invited to test out the new system firsthand. Everyone was encouraged to step aboard the “boat” and compare the two different access ladders.

“The innovative side step access ladder for transferring workers between a vessel at sea to a fixed structure in U.S. waters satisfies current OSHA regulations while providing a safe worker space, as defined by OSHA, between the surrounding fender structural members and the vessel bumper,” says Rudolph Hall, managing principal of Keystone Engineering, “showing that this innovation balances U.S. specific requirements and making sure that workers are safe at sea.”

By demonstrating this U.S. innovation as part of DOE’s advanced offshore wind demonstration projects, this access ladder could be adapted to projects around the world, improving the safety of offshore workers globally.

Through targeted investment in research, development, deployment, and market barrier removal, DOE is working to promote the responsible development of a world-class offshore wind industry in the United States.

“Alstom is partnering with several DOE offshore wind projects,” says Andy Geissbuehler, general manager of GE's Alstom Wind North America. “These projects, as well as other DOE offshore wind efforts, are vital and highlight the significant potential of offshore wind in the United States. Deepwater Wind’s Block Island Wind Farm, the first commercial wind farm in the U.S., will feature GE’s Haliade 150 6-megawatt turbines. This historic project, as well as the Dominion demonstration project off Virginia Beach, exemplify the investment and innovation that are essential as we develop new technologies to power America’s clean energy future.”

Read more about the Wind Program’s offshore wind research and development efforts.