Replacing Solar thermal and natural gas with Solar PV and electric pool heater

[BigDave]

See if you can find out about the hybrid watercooled PV - it sounds pretty cool.

[mas985]

PV only makes sense if you are using it to offset current electrical usage and even with that, payback is usually over 10 years.

Also, the combined efficiency of PV with a heat pump, is about the same as the heat transfer efficiency (BTU/sqft) of passive solar so you will need a PV solar panel about the same size as your current pool solar panel to get the same amount of heat. Therefore, you would not be gaining anything using PV to heat the pool and given the up front cost, it would be costing you a lot of money. For those days where you do not need to heat the pool, you would offset some house usage but that will may not be enough to justify the cost.

The water cooled PV might be a better option but I suspect that the heat transfer to the water is a lot less than passive solar.