My friend, a very smart geologist was showing me his Active Solar Water Heater system. He’d run calculations figuring how much money he was saving with it. (We’re in New England if it matters)
I then asked if he had accounted for the cost of electricity to run the circulator pump. After an embarrassed reaction it was back to the calculator and he realized he was actually losing money.
With just a little googling I found most analyses focus on the cost of equipment and factor in the use of a ‘backup’ system for cold seasons or when no sunlight is available. But I don’t easily find any accounting for the accompanying electrical energy usage.
So, what’s the scoop? Are they worth it in ‘Northern’ areas?
I did find this source
that says recent improvements in Photovoltaics make liquid collectors obsolete; just use PV panels to heat the water directly, without an intermediate exchanger.