Multi-criteria optimization of an experimental system for the production of domestic hot water

An experimental domestic hot water (DHW) production system, composed of a heat pump, a heat storage and a heat exchanger is considered for this study. The IUSTI laboratory test bench recovers heat from the air extracted from a collective dwelling using a heat pump. The heat is then transferred through a heat exchanger towards a thermal storage for DHW needs. A simplified model, validated experimentally, is used to simulate the energy system. Then, a multi-criteria optimization is applied with genetic algorithms to optimize regulation and design parameters and more particularly the influence of the DHW demand profile. The objectives are to maximize the coefficient of performance and to minimize the auxiliary electrical energy. The solutions obtained must take into account constraints of the test bench and the optimization problem. Finally, a sensitivity study, based on factorial plans, is achieved to determine the set of parameters that has the strongest degradation on the objectives from the optimized solution. The optimization methodology is validated and leads to a significant improvement of the system effectiveness. Indeed, the optimal solution from the test has a gain on the coefficient of performance of 6.9% and on the auxiliary energy of 25.2% compared to the reference solution.

Automated summary

This study investigates an experimental domestic hot water production system that uses a heat pump to recover heat from the air of a collective dwelling and transfer it to a thermal storage for hot water needs. A multi-criteria optimization approach is applied to optimize the system parameters, with a focus on the influence of the hot water demand profile. The optimization methodology is proven effective in significantly improving the system efficiency.