The Weekend Wonk: Interest High in Offshore Wind – from Maine to the Great Lakes
April 28, 2012
New video on wind power coming very soon. In the meantime, the video above tracks efforts to deploy wind offshore in Maine’s chilly waters. An equally enormous resource awaits in the Great Lakes, which developers are eager to tap, see below.
Some sustainable resources are simply ripe for the harvest. According to Wind Energy News, a September 10 report from the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) offshore wind resources have a total potential of 4,150 GW.Translated, this amount of offshore wind could provide roughly three times the current total U.S. annual electricity demand.
MUSKEGON, MI – Out of sight is out of mind, offshore wind proponents hope.
Two Michigan universities have joined forces with a Seattle-based design company to pursue offshore wind technology that could be a “game-changer” on the Great Lakes.
Grand Valley State University and Michigan Technological University are in a group seeking federal funding for initial engineering and design of new floating-turbine technology. The floating technology has the potential of moving turbines to the middle of the lakes.
The public-private partnership is seeking investors to cover the matching funds needed in a U.S. Department of Energy wind technology grant program, GVSU officials said.
The Glosten PelaStar floating wind turbine platforms would allow placement of utility-scale wind farms anywhere on the Great Lakes and in water depths that would allow the turbines to be located so they cannot be seen from shore.
The past debate over wind turbines on Lake Michigan centered on opposition to near-shore turbines that are clearly visible from shore. The Scandia Offshore Wind project proposed for the Lake Michigan waters off Oceana and Mason counties created a huge public outcry that led both counties two years ago to reject the concept.
Current turbine anchoring technology cannot be used in deep water, forcing the wind turbine towers to be placed within six miles of shore in areas off Muskegon. Turbine towers would have to be 22 miles out into the lake to be completely invisible from shore.
With the PelaStar floating system, no problem says its chief engineer.
“I get it … I understand how waterfront property owners feel about turbines in front of their houses,” said Charles Nordstrom, the senior engineer on the Glosten Associates PelaStar project who grew up on the shores of Lake Erie. “The Scandia project had a chilling effect on offshore wind in the Great Lakes. With PelaStar, we are going to melt that chill.”
Michigan Tech’s Great Lakes Research Center is the lead agency requesting funding from the Department of Energy in a U.S. offshore wind demonstration project. The Michigan Tech group includes GVSU’s Muskegon-based Michigan Alternative and Renewable Energy Center, along with Holland-based turbine blade manufacturer Energetx Composites and Muskegon-based Andrie Specialized, a marine transportation company.
“With offshore wind, 80 percent of the problem is visibility, which is a big issue,” said Arn Boezaart, MAREC director and member of the former Michigan Offshore Wind Council. “This is technology that wants to be in deep water, not near shore.”
PelaStar is a floating wind turbine platform technology that Glosten has been developing for six years. The submerged platform tied to the lake bottom or ocean floor with permanent anchors has been “tank tested” but the West Coast company is looking in several areas of the world – including the Great Lakes — to put up a full-scale prototype, Nordstrom said.
The PelaStar technology is known as “tension-leg platforms.” The turbine tower actually sits on a platform about 50-feet below the surface. Below surface, the platform is not moved by waves or ice, Nordstrom said.
The platform is highly buoyant and is kept in place with “tendons” attaching the platform to lake or sea bottom anchors.
The tension between the platform, which wants to rise, and the anchor system makes for a stable base for large turbine towers, Nordstrom said. This is proven technology that has been used in the offshore oil and gas industries but is being modified for wind turbines, he said.
“The wind turbine will always stay vertical and it performs as if it was anchored,” Nordstrom said.
The PelaStar system offers several economic advantages for offshore turbine installations, Nordstrom said.
First, Glosten estimates that cost of the PelaStar system is up to 25 percent less than offshore foundation systems now being used in Europe.
Secondly, the floating system allows for much deep-water deployment of the turbines in areas where wind is stronger and more constant than closer to shore, Nordstrom said. Offshore tower placements away from shore will allow the turbine to produce more power, but the drawback is the transmission cost of underwater cables and the distance work crews need to travel to maintain the devices.