Sept. 20, 2011

Harsh winter weather on the Great Lakes takes a toll on offshore structures.

ANN ARBOR, Mich. ­– In an effort to better understand the market barriers to offshore wind energy, University of Michigan researchers will examine the impact of ice on power-generating turbines operating offshore in the harsh winter weather of the Great Lakes.

The Department of Energy  (DoE) recently announced funding for two U-M studies that will explore the effect of ice at the water surface and above on the potential collection and distribution of power by offshore wind turbines. The researchers’ work will concentrate on the Great Lakes, and are among $43 million dollars in DoE grants provided for 41 wind energy projects nationwide. The studies are launched to speed technical innovations, lower costs and shorten the timeline for deploying offshore wind energy systems. The U-M work includes:

• A $400,000 grant to develop computerized modeling tools that will simulate surface water ice and the impact of ice-loading or pressure on offshore structures. The analysis will inform the design of turbines that could be deployed at varying depths in Lake Huron and Lake Michigan. According to the project lead, Professor Dale Karr, similar work had been conducted for offshore oil production in the Arctic Ocean in the 1980s and ‘90s.  As interest in Great Lakes offshore wind power increases, comparable analyses are demanded for this unique freshwater environment. “If we’re going to be building structures in the Great Lakes, the impact of ice needs to be studied here,” Karr said, noting that ice can cover nearly 100 percent of the Great Lakes’ surface in harsh winters.  In addition to the U-M, the Karr-led team includes the National Renewable Energy Laboratory, Keystone Engineering Inc. and the American Bureau of Shipping and Affiliated Companies.

• A $690,000 award to analyze seasonal trends and conduct field measurement related to ice, wind and wave loads on fixed offshore structures. Measurements will be assessed at the water surface level and above, where atmospheric icing can collect on turbine blades. The project is led by Professor Guy Meadows, director of the Ocean Engineering Lab. Field measurements will be collected during the next two winters at such existing “structures of opportunity” as the light stations off North Manitou Island or in similar harsh and exposed regions. “These projects are all about exploring the market barriers to offshore wind,” Meadows said. “The impact of icing is a major question that must be understood if wind power is to be harvested from the northern lakes.”

The investigations are closely related to a joint U-M, Grand Valley State project that will study the feasibility of offshore wind power on Lake Michigan based on data collected by a massive research buoy slated for deployment this fall. Meadows is the U-M’s lead investigator on that project.

Contact: Paul Gargaro, Michigan Memorial Phoenix Energy Institute, 734-615-5678, pgargaro@umich.edu