2022-017 - Aishihik Hydro Unit #1 10-Year Teardown and Overhaul

Yukon Energy Corporation (YEC) has a three-unit hydro-electric generating station approximately 150 Km north-west of Whitehorse, Yukon at YEC’s Aishihik Hydro site.

The Aishihik Hydro powerhouse is an underground plant, located approximately 460 ft beneath the service building. Personnel and small equipment access to the powerhouse is via a service elevator. Larger components can be moved in and out of the powerhouse using a larger access shaft and overhead crane located in the service building.

AH1 is a Francis style, vertical shaft turbine-generator with a generator rated output of 17.28 MW originally installed in 1973. AH1 has a mechanical gate shaft governor with AH1 was last overhauled in 2012. An upstream turbine inlet valve (TIV) provides certified single device isolation. Downstream, a single vertical lift tail race gate provides certified single device isolation. YEC will be establishing and maintaining the isolation for the duration of the outage, however the Contractor may be called upon to assist with installing pumps, operating valves and monitoring water levels as required.