Description: An apartment building has a pumped ring main that circulates hot water at 75 C through insulated 40 mm pipe with heat loss of 17 Watts/metre. At each apartment, this hot water is mixed with cold water to a delivery temperature of 50C? One of the sub-questions provides extra info: It takes 0.00119 kWh/degree/litre to heat water from 15C to 50C.
My problem:
With typical water-efficient shower and taps, typical Melbourne usage of hot water is 44 litres/day/person. For typical occupancy of 1.8 people, what is the effective efficiency of this hot water distribution system (for simplicity assume the existing heating system feeding the distribution system is 100% efficient).? Note that this efficiency calculation ignores the efficiency of production of hot water.
If anyone can help me or if anyone has any idea that would be great!
Thanks :)