The developer, Dakota Plains Energy, is lining up landowners in Gregory County - just west of the Missouri river in south-central South Dakota - to host hundreds of turbines. From there, transmission lines could potentially cross the river at its narrowest point and travel 1,000 kilometres eastward to Chicago. But although two companies intend to build a major South Dakota transmission line, specific routing is still being studied by the Midwest Independent System Operator (Miso).
"It's very much a chicken-and-egg scenario," says Matt Kaplan, a senior analyst at IHS Emerging Energy Research. "It's tough to build wind projects before you've got the transmission. But someone has to take the risk and in the end, hopefully, they'll be rewarded. This is an issue that's increasingly going to face the US market in regions like the Dakotas."
Key to the new transmission is the US federal government's recent approval of a cost-allocation method allowing Miso to create so-called multi-value projects (MVPs) - likely to result in 20 or more major lines by spreading costs to ratepayers throughout Miso's 13-state footprint
The two transmission builders - Electric Transmission America and International Transmission Company (ITC) - intend to build South Dakota lines that combine 765kV and 345kV wires, along with lower-voltage enhancements. Both companies are open to combining their plans and expect to gain MVP status. The new transmission would support up to 12GW of wind and other generation. But construction may take three years or more after Miso determines the route and grants final approvals.
One complication is that, by crossing the Missouri river, new transmission must pass between regional operators - which means Miso will need to establish atypical ties with the Western Area Power Administration. "For this to be successful it needs to be done through partnerships and agreements," says Terry Harvill, ITC vice-president of grid development.
Meanwhile, Dakota Plains president Rob Johnson believes he can attract Miso's transmission planners while involving landowners and other citizens via ownership shares beyond lease payments attached to the $2 billion wind development. Johnson drove thousands of kilometres around the state in recent months to find an ideal location and expects the project to be built in several phases over at least seven years. "Nothing is going to happen overnight," Johnson says.
Sparsely populated South Dakota ranks fourth among states in wind potential but 16th in online capacity with 709MW. Gregory County and other desolate counties west of the Missouri boast some of North America's best untapped wind resources.