In addition, the company has applied for a presidential permit from the U.S. Department of Energy for the international interconnection at the US-Canadian border.

The latest transmission line will deliver emission-free hydroelectricity generated by Manitoba Hydro for Minnesota Power customers and the upper Midwest clean.

Total estimated cost for the project, including substation work, is between $500m and $650m, depending upon the final approved route.

The project will assist in providing at least 750MW of energy into the US starting in 2020.

Minnesota Power COO Brad Oachs said, "The Great Northern Line enhances a unique synergy involving hydropower and wind.

"The new transmission capacity more readily allows the Manitoba Hydro system to store intermittent wind generation during times when energy markets don’t need it.

"This is important to Minnesota Power as we expand our Bison wind project to 500 MW in North Dakota by the end of this year."