The standby isn't going to be very much, when compared to those two cartridge pumps
running almost the whole time the sun is on the collectors.
The motor run-time might be lower, if you used a small storage tank, or kept
using hot water all day.
We had three full sized Novan collectors and used an 84 gallon tank.
In the winter, it would average about 120 deg F.
In the summer time, I think it was about 30 or 40 degrees warmer.
One could just use a
Sun detector gizmo to power up the system every morning
when the sun started warming things up..
Edit:
Maybe even a timer? Have the AC switch off at night.
If I was going to use this again, I would use a
Sun detector/Switch
It would control the AC to the hotwater system with a SS relay (Solid State)
that was being driven by a small PV panel.
At night, or when it was very over-cast, the system would go into shutdown.
Zero watts on standby!
