Pre-stored supercapacitor energy as a solution for burst energy requirements in domestic in-line fast water heating systems

Delayed hot water in domestic water heating systems is a worldwide problem. In New Zealand, it accounts to over a 15 million cubic meters of treated water wasted per year. There are few commercial solutions proposed to minimize the problem, but none of them are affordable or practically convenient. To increase the temperature of stored water in buried pipes by 20–30 °C at an average flow rate of 5–8 1/min estimated power is over 15 kW. The circuit breaker in a 230V/50 Hz, 10 A domestic sub-circuit creates a barrier for this application to be solely powered from the 230 V mains. A supercapacitor based high-kW pre-stored energy transfer system can solve this environmental issue of wasted water and the repeated frustration in the kitchen or the wash rooms on a daily basis. This paper provides the fundamental justification for such a low-voltage electrically-safe short duration localized in-line water heating solution with high instantaneous power capability. Initial test results of a proof of concept prototype, with "fast-energy-delivery, replenish-gradually, and ready-to-go" basis design shows the effectiveness and the practicality of the supercapacitor solution, leading to a commercial product design.