Well, i was thinking about that too, but the neighbors would likely kill me for having this thing running for days (they use firewood) and i just can't sleep in noisy environments. It's a nightmare on intercontinental flights. As soon as i recognize the noise cancellation of the ears at the moment i'm falling asleep, i wake up because the absence of turbine noise is raising some kind of alert. Maybe i shouldn't have tried to forcefully stay awake for quite some time, in an episode of my past life. IDK  

Sorry, drifting off topic a little...
The big plus of the PV cells is that you feed the unused power into the supply network, which saves and sometimes even generates some good amount of money.
It just has to be big enough to run the house on a semi-clouded day. A dry, floating room (room in a room), dug into the ground for a tank and generator that could run for days would cost much more, but this would be the minimum.