I'm looking for help on how to set up about 1-2kW of solar panels to heat a hot water tank of 250 Litres using (probably) a 24V or 48V 600W heating element. (I'm in New Zealand, South Island, so I wont be getting all that much bright sunshine.)
Please can you point me to somewhere on the website that explains the simplest and cheapest way to set up a controller to work at the array's maximum power point and limit voltage to 24V or 48V at the output? At this stage, I'm not thinking of charging batteries as well, so don't need any overflow system to divert surplus energy to the heating element. I've been thinking of using a normal lead acid battery charge controller and setting absorption and float voltages to 24V or 48V, but wonder how the charge controller would behave when set up like that, since the heating element would not behave like a battery nearing full charge.
Your home page says "If all you need is to heat a bit of water with the excess from your small (less than 3kWh) PV array then that can be done with SBMS and some external SSR." Is there somewhere on the website that expands on that idea?