I also have a diesel generator that is only used in summers for running two airconditioners and to recharge the battries in the inverter set up in case of a longer then usual power cut. For water in winters we have a two solar water heaters 200litres each set up in series to work as a single unit. Two solar water heaters are supposed to give better results as compared to one larger capacity one. I have no idea how true that is because I cannot compare.
What do you guys use at home and what would be your dream set up for power back?