No, when we talk about hydro storage, it means not operating your unit. So you don't run your water; you buy from somewhere else when it's cheap. It's the same thing as storing that electricity.
In the case of Hydro-Québec, if it buys out of the Ontario market, it won't run its facilities. That power will power part of industry, and it could be in Montreal. Then when the price in Ontario comes up, it'll stop buying out of Ontario and then it'll run its own facility. It's the most efficient form of energy storage.
A lot of what's coming out of Ontario now was produced out of wind, an excess produced out of wind and nuclear overnight. So it's very efficient, because you're just not operating and then when you have.... Hydroelectric is very efficient to begin with. Pump storage is less efficient because you actually have to pump the water up.