K, you are entirely correct. I currently use a 1500W internal heater to heat up the water when I purify the water in the water purifier. It makes no difference to the equipment as to where the electricity comes from. Last month when I went to Bonnaroo again, I took my 230W solar panel, 5 100Ah batteries, and my 5000W inverter to run my portable AC unit...it’s the same principle.
When I have the extra positive cash flow, I plan on installing along with the solar panels, I plan on installing
2 solar evacuated tube solar hot water heaters and a solar hot water tank. Again, same principal, just using Mother Nature to heat the water for me.