We always intended that our next house would have a solar hot water system. It's seems crazy not to when the sun shines so much of the time where we live.
Now that we're in the throes of this renovation we've had to slightly re-think that plan. We know we'll be renting this house out. We don't have natural gas here so the hot water back up would have been instantaneous gas fueled by a gas bottle. We've decided we're not comfortable with having a gas bottle in a house that will be tenanted. Maybe we're worrying about nothing but we both had this same thought separately. The decision was easy - an off-peak electric hot water service.