The ±500 kV Bipole III high-voltage direct-current (HVDC) power converter stations for Manitoba Hydro are complete. The line will deliver renewable energy to southern Manitoba and the United States.

The stations are part of the Manitoba Hydro Bipole III transmission project, which is intended to bolster the reliability of Manitoba's electricity supply by reducing dependence on existing HVDC transmission lines and converter stations. The new facilities also are expected to better ensure low-loss transport of renewable hydropower from northern generating stations.

HVDC converter stations are specialized substations that support converting electric power from high-voltage alternating current (AC) to high-voltage direct current (HVDC), or vice versa, a critical component to interconnecting separate power systems. HVDC transmission typically suffer much lower electricity losses than standard AC transmission.

The Bipole III converter stations include the Keewatinohk Converter Station in northern Manitoba near Hudson Bay, and the Riel Converter Station near Winnipeg in the southern region of the province. The converter stations have a transmission capacity of 2,000 megawatts (MW). The facilities were built by Siemens and Mortenson Construction.

Siemens delivered the system design and the manufacturing, supply and commissioning of the core HVDC technology. Mortenson provided design support and construction services for the supporting infrastructure, including converter station building, AC filters and DC switchyards.