Maybe there is a typo in the power of the water heater, 15000wh (15 Kwh) seems way too much, a typical water heater (at least here in Italy) is 1.6 or 2 Kw (not

Maybe there is a typo in the power of the water heater, 15000wh (15 Kwh) seems way too much, a typical water heater (at least here in Italy) is 1.6 or 2 Kw (not Kwh btw). In off grid situations are common "hybrid" water heaters, with either a plain enough solar serpentine or with a heat exchanger connected to the wooden stove.