Yeah diversion controllers are great for off grid. I had one for my wind turbine because they need to stay loaded. But even with solar, most off grids are over paneled a lot, so when rh sun is out u can get quite a bit of energy for water heating. The two main diversion controllers are the xantrex and the tri star. The midnight classic has some nice functions such as a programmable PWM output that can control a SSR.
Well I know I said "free", but if the modules are not free but just cheap, maybe one would want something more efficient than a direct connection to a resistor. Also I didn't say the racking was free, so there is that. Of course one would have to weigh all this out for a given set of circumstances.
Very clever!I just found a published paper where someone delves into using diode chains for heating from solar panels:
Hot diodes!: Dirt cheap cooking and electricity for the global poor?
Direct DC Solar (DDS) electricity can inexpensively cook food and charge appliances. Insulating the cooking chamber allows the food to cook with a low…www.sciencedirect.com
I don't remember if they ever said. This was many years ago, who knows if these systems are still being sold. I did a quick internet search and the results were all solar thermal systems.
