Those other options might work, but add complexity...I have overpaneled my solar system, so if there is sun, there is plenty of extra power for my modest energy needs. That is why I am trying to use the extra energy for heating.
I have thought about adding a few more panels and doing some direct-from-PV heating with no batteries/controller/inverter. Its interesting what you can do these days with panels being so inexpensive and everything getting pretty efficient...
