Second DC tie line proposed to connect Saskatchewan, Alberta

Rocky Mountain Power (RMP) and partner LECTRIX LLC are in the early stages of development for a proposed merchant transmission line that would connect Saskatchewan and Alberta.  

“Saskatchewan and Alberta have one back-to-back DC tie at McNeil (Alberta), and we’re looking at putting in a second back-to-back DC tie at Lloydminster,” RMP managing director Lorry Wilson told TransmissionHub on April 2.

The Saskatchewan-Alberta Tie Line (SATL) project includes the proposed 150-MW back-to-back DC transmission link connecting Alberta and Saskatchewan, as well as about 10 kilometers (6.4 miles) of 230-kV transmission line to connect the intertie facility to Saskatchewan’s AC grid.

The back-to-back intertie facility in Lloydminster, Alberta, about 250 kilometers (155 miles) east of Edmonton on the Saskatchewan border, would be all in one building. “You bring the 144-kV AC [from the Alberta system] on the Alberta side,” route it through the back-to-back DC converter, and “on the other side of the building, we’ll build 230-kV AC to connect to the Saskatchewan grid,” Wilson said.

LECTRIX and the RMP management team have previously worked together to perform the initial development work for the Montana-Alberta Tie Line (MATL) project.

SATL will use newer voltage source converter HVDC technology, but Wilson said other questions remain to be answered. “Route selection and the AC technology, whether it’s monopole, single pole, or underground, the jury’s still out on that,” Wilson said. The cost for an aboveground option is estimated to be between C$100m -C$120m (US$101M  – US$121.1m). 

The line is being built using private funding, and Wilson said RMP and LECTRIX are bringing on some additional, major capital partners.

The SATL team is currently negotiating with anchor tenants for up to 50% of the total capacity; the balance will be offered through an open season process.

SATL is anticipated to provide regional reinforcement alternatives, enhanced reliability to both Alberta and Saskatchewan, as well as increased operational flexibility to manage the integration of greater renewable resources into both provinces.

The target in-service date is 4Q15.