I'm calculating the size of the hot water accumulators for a condominuim. I know that the use of hot water is ~ 0,5 l/s (probability considered). The water is heated by an external hot water source through a heat exchanger. What I've done is to calculate the heat supply capacity using; 4,2*70*0,5 = 147 kW I'm not really sure what to do with this number, or if I need it at all. How can it bring me closer to finding the required volume of the accumulators?