The project would cost $10 billion to $12 billion. It includes two 765-kilovolt transmission lines through Iowa, and a third along the Minnesota-Iowa border that could go through either state.
A lack of transmission links has been one of the major obstacles to development of wind energy in the Midwest. Without adequate transmission connections, wind farms often aren't built in the best areas, or are not built at all.
"Right now, people are developing wind farms where they can get the transmission connections and not where the most optimal wind resources are located," said Doug Collins, executive director of ITC Holdings' ITC Midwest subsidiary in Cedar Rapids.
Collins said the system also would enable the transmission grid to "get ahead" of wind farm developers, solving a time lag problem in the construction of transmission lines.
"It takes us about two years to get the transmission in place, and they can typically build a wind farm in about one year," Collins said. Until the transmission system is beefed up, new wind farms sometimes operate at partial capacity, Collins added.
The project would build 765-kilovolt transmission lines stretching from wind farms in South Dakota, North Dakota, Minnesota, Iowa and Illinois to major "load center" cities including Des Moines, Minneapolis-St. Paul, Madison, Wis., and Chicago.
From the Chicago area, existing 765-kilovolt transmission lines can transmit the power to points further east.
Completion of the project will depend largely on whether the Federal Energy Regulatory Commission approves transmission tariffs that would allow ITC to pay for the project with an adequate rate of return. Another issue will be approval from state utility regulatory commissions. They would have to recognize the project as a public good in order for ITC to buy land from property owners that are not willing sellers.
ITC, based in Novi, Mich., acquired the transmission system of Interstate Power & Light Co. in late 2007. It expects significant state support based on the goals of the Upper Midwest Transmission Development Initiative to improve transmission linkages for green energy. The latter has the support of governors in five states, including Iowa.
ITC expects the process to take years. It plans to start talking with stakeholders, beginning with the Midwest Independent System Operator, which addresses power grid reliability issues in a large part of the Midwest.