Scanning through the link you provided, there's a discussion of interties between neighboring provinces, but there's no way the plan here is to replace Alberta's natural gas with hydro from Labrador, 5 provinces to the east.

There's also an acknowledgment of the continuing need for natural gas (possibly for political reasons). But even in a future where natural gas is phased out, it would be much more logical to use hydro from BC or MB. Alberta could also increase its own solar and wind.