SIOUX FALLS, S.D.
Transmission lines originally slated to carry coal-generated power from the scrapped Big Stone II plant could open up a new market for proposed eastern South Dakota wind farms.
Big Stone II's plans had called for new and upgraded high-voltage power lines in southern Minnesota to carry power to customers to the east from both the 550-megawatt coal-fired power plant near Milbank and nearby wind farms.
The Midwest Independent Transmission System Operator has identified about 1,900 megawatts, enough to power some 500,000 homes, of potential wind projects that could jump on board an upgraded transmission system.
One project accepted into the Midwest ISO study is Dakota Wind Energy, a 300-megawatt wind farm planned for Day, Marshall and Roberts counties, just south of the North Dakota border.
"They're creating more of a backbone transmission line that will serve not just one generator but a number of wind farms in the area," said Ben Kerl, a senior wind developer with Dakota Wind Energy's managing partner National Wind LLC.
Bismarck, N.D.-based Montana-Dakota Utilities Co. and Fergus Falls, Minn.-based Otter Tail Power Co. were two leading partners in the planning of Big Stone II, which was more than four years in the making. The project was canceled in November, with developers citing financing problems and the possibility of new federal carbon dioxide restrictions.
The Midwest ISO, a regional power-grid agency, immediately stepped in to salvage the transmission line portion of the project.
Steve Wegman, executive director of the South Dakota Wind Energy Association, said transmission upgrades could inject new life into projects proposed along the Coteau Des Prairies ridge of northeastern South Dakota.
Building wind farms without transmission lines is like building cars with no roads to drive on, he said.
"It gives our state an economic development tool to sell wind energy into the Minneapolis area," Wegman said.
Eric Laverty, Midwest ISO's director of transmission access planning, said although only 1,900 megawatts of projects qualified for inclusion in the study, the agency estimates that a system of upgraded lines could carry as much as 2,400 megawatts of power.
"If another 500 steps forward, we'll do our best to catch them up," Laverty said.
Midwest ISO hopes to complete its study by August, establishing a transmission plan to connect those 1,900 megawatts to the grid. The next step would be to pinpoint what it's going to cost and how long it would take to build. The Indiana-based agency is hoping to keep the cost of transmission upgrades to be shared by the power providers to around $200,000 a megawatt.
Wegman said the nation hasn't made any big investments in transmission since the 1970s.
"That's like having your house and not putting any shingles on it for 40-some years and hoping that it doesn't rain or hail," he said.