Why would Enmax pay for individual batteries in people's houses vs grid storage? Grid storage is much more efficient, and gives them control.
It may make sense to utilize batteries individuals purchase if they want to sell it back, but paying to put them in people's homes makes little sense.
Before we go paying for solar on people's homes, we should maybe force companies to utilize their vast amounts of empty rooftops. The could store the excess power onsite, and dispatch as needed. Similar to what you are suggesting, but on a scale that makes sense. I'm amazed we don't require solar over a certain flat sq footage roof. Look at all this brand new wasted space.
https://goo.gl/maps/yYjsptgYf2QwMNKo7
This is the only solar installed, and just south are 2 massive buildings that dwarf the space capacity, not to mention all the space west of there.
https://goo.gl/maps/ovsGMJ9nnDwVCREz6