HOUSTON—Technology used by the oil and natural gas industry including jackets and tension-leg platforms (TLPs) have benefited the offshore wind industry, which could provide a power source that could help fill electrical generation gaps in the U.S.

Alana Duerr, the lead for offshore wind within the Wind Energy Technologies Office at the U.S. Department of Energy (DOE), said the DOE’s goal is to build a business case for the resource, address challenges and help reduce costs, enabling development in all coastal regions and optimizing grid integration and transmission.

The gap between current energy generation from existing U.S. wind facilities—land-based and offshore—and growing electricity demand is about 2,400 terawatt hours per year by 2050, Duerr said at OTC 2017. “While offshore wind has the resource to fill all of that, we’re not suggesting that it will. We’re suggesting that we want offshore wind to be part of the mix that actually fills that gap by 2050.”

Duerr noted there would need to be a “significant amount of upgrades to transport electricity from the middle portion of the country where there’s a lot of really good land-based wind resource, out to the coast where there’s the energy demand. So that’s why we’re looking at places off the East Coast that have the population density, the electricity demand and also the offshore wind resource.”

Much potential lies on the nation’s coasts, where about 80% of the electricity demand is centered, she said. “Off of those regions there [are] approximately 2,000 gigawatts [GW] of offshore wind energy that could be accessed and exploited with the technology that we have today,” she said.

The U.S. has land-based and offshore wind potential, and Duerr noted that coastal areas have grid infrastructure to support it, making them the best places for development. While the Midwest has “a lot of good wind resource,” the region lacks “the grid infrastructure to support bringing that energy …. to any other market.” She also noted that Texas, which has “the most land-based turbines in the entire country,” also faces the Midwest’s problem.

The nationwide resource of 2,085 GW of electricity is technically accessible through existing technology, Duerr said.


“The U.K. North Sea, Denmark, the Netherlands and Germany are very bullish on offshore wind,” she said, noting Statoil ASA (NYSE: STO), Royal Dutch Shell Plc (NYSE: RDS.A), DONG Energy, Eni and Total work in the sector.

With nearly 4,000 turbines in the North Sea, Europe’s installed capacity was 13 GW by year-end 2016. That year $24 billion was invested in offshore wind in Europe, she said. Today, 6 GW are being installed, and just over 230 GW of projects are in production development.  


In the U.S., offshore wind is finally taking hold, Duerr said, noting the five-turbine, 30-MW Block Island project off Rhode Island became “the first project in the water” in 2016. About 13 GW worth of projects are in various stages “from site control all the way through to negotiating [power purchase agreement] with the recently announced deepwater wind [Northwood] project that is going to be connecting into the Long Island grid.”

 “Beginning in November 2010 with the Cape Wind project, nearly one-quarter of a million hectares (222,004 ha) have been leased on the U.S. Outer Continental Shelf (OCS) for potential offshore wind power development in the Northeast. More than $4 million in bonus bids were accepted for these leases. Projects have been moving forward slowly, and none is expected to be fully implemented before 2020,” according to “Northeast Ocean Planning Baseline Assessment,” a September 2016 report from Ocean Planning in the Northeast.

DONG Energy, Copenhagen Infrastructure Partners and other companies are starting to seriously invest in the U.S., Duerr said, adding Statoil recently purchased a wind energy area offshore New York for $43 million. The key player in U.S. development on the federal side is The Bureau of Ocean Energy Management, she said.

The largest commercially installed turbine offshore is Vesta’s 8-MW, 164-m diameter turbine, Duerr said, noting turbines are growing in size; four years ago the largest diameter was 130 m. “These turbines are getting really big, so they need vessel infrastructure to install them,” she said.

As the turbines grow larger and require vessel installation help, they are also utilizing jackets, spar floating foundations, semisubmersibles and TLPs, technologies all native to the offshore oil and gas industry.

Duerr said the offshore wind industry continues adapting and innovating on borrowed, mature oil and gas offshore technologies, as well as technologies from land-based wind. Costs are dropping rapidly and becoming competitive, and utilities are getting in on the action. Duerr mentioned that Dominion Power was involved in one offshore wind advanced technology demonstration project.

The DOE has focused on demonstration projects over the last four years, she said, with the goal of driving down costs by de-risking innovative technology, including using floating platforms, different types of foundations and the largest turbines available. In 2013, there were seven of these projects, including three floating projects.

There are currently  two projects, Duerr said:

  • The University of Maine’s deepwater floating project 2.5 miles off of Monhegan Island in state waters. Two concrete semisubmersibles will deploy by year-end 2019, utilizing the GE 6 MW turbine; and
  • LEEDCO in Lake Eerie. A subsidiary of Fred Olsen is developing the shallow-water project about 7-10 miles off of Cleveland. The project will need to combat surface ice and weak, muddy soils and bedrock. A monopile that will be rock-socketed is being considered, but this would not be cost effective for a commercial project. Another option is a monobucket developed by Universal Foundation that will provide lateral resistance and withstand soil.

Jobs And Environment

If the sector develops as experts have projected it will,  43,000 permanent jobs supporting offshore wind in the U.S. could be created in about 20 years, Duerr said. Jobs include manufacturing, installation, operations and maintenance, she said.

In addition, offshore wind can combat the “not in my backyard” issue with energy infrastructure projects, Duerr said. Wind energy projects can be moved farther and farther offshore until they cannot be seen from the shoreline, she explained.

She also said wind energy produces fewer greenhouse gas emissions than other forms of energy generation, and noted that the price would remain fixed. Over the 20- to 25-year lifetime of an offshore wind project, the fuel price remains consistent through the power purchase agreement, benefiting the overall economy.

Erin Pedigo can be reached at epedigo@hartenergy.com.