Specialized wind installation vessels provide the backbone to wind farm creation. But the Great Lakes greatly complicates use of these increasingly sophisticated — and expensive — purpose-built vessels.
Limitations posed by the Saint Lawrence Seaway are the biggest impediment. Because of its locks, the seaway requires ships to have a maximum vessel beam size of 22 meters or 78 feet. The latest generation of wind farm installation vessels are almost three times that.
“Bringing open ocean vessels through the Seaway is a non-starter,” said John Kourtoff, CEO of Toronto-based Trillium Power Wind Corp., which has been attempting to develop wind farms on Lake Ontario for almost two decades. “We knew that from the get-go.”
In 2008, as it was ramping up development efforts, Trillium turned Glosten Associates Inc., the Seattle-based naval architecture and engineering firm, to come up with two separate barge designs. The first was for foundation installation. The other was for installing the towers, nacelles, and blades. That barge would serve as a maintenance vessel as well.
Glosten’s designs hinged on the ability to lock together multiple sections, each of which was narrow enough to traverse the Seaway. The vessel, with locked sections, must be as rigid as if it were one.
The design for the installation barge included a 110 meters crane, helipad, and crew quarters for over 40 workers. Kourtoff said he even mandated that jackup legs and other articulating components use non-polluting lubricants made from vegetables.
According to Kourtoff, “the reason for us to put so much capability into our barges” was to benefit from first mover advantage. Trillium, in addition to its highly publicized initial venture, has identified three other wind farm sites. The company could lease out these vessels to other developers as well, Kourtoff said.
“Our designs were so unique that we have had inquiries (via The Glosten Associates) from several global companies that have supplied many, many offshore wind developments around the world with wind turbines,” Kourtoff wrote in a follow-up email. “They, too, have run into the issue of how to install in The Great Lakes.”
Another complicating factor for installation vessels is the Jones Act, which mandates US flag carriers for operations between US ports. That applies to Great Lakes shipping within the US as well. That means for wind farms in U.S. lake waters, domestic-made barges must be used. That will most probably limit the size of the turbine to about 6MW, or half the power of the newest generation of offshore turbines.
“Given physical vessel size constraints of the lock systems getting into and between the Great Lakes, to a large degree, major components for offshore wind could not be leveraged for use in the Great Lakes and a separate supply chain would need to be developed,” said a spokesman for the New York State Energy Research and Development Authority, or NYSERDA, which is in the midst of conducting a feasibility study on the potential of Great Lakes wind energy.