Numerical analysis of the impact of water temperature setpoint and energy strategies on indoor pool performance

TL;DR

This study analyzes how water temperature setpoints and energy strategies affect indoor pool energy use, identifying key phenomena like evaporation and testing strategies that can reduce energy consumption by up to 17%.

Contribution

It introduces a phenomenological steady-state model and evaluates two energy-saving strategies for indoor pools, including night setback and thermal solar panel optimization.

Findings

Night setback with precise restart yields 4% energy savings.

Overheating pool water by 1°C can save up to 17% energy.

Evaporation and dewpoint are key factors influencing energy use.

Abstract

Indoor swimming pools (ISPs) consume significant amounts of electrical and thermal energy to ensure the heating of water and air, ventilation, and maintaining adequate humidity levels. This is measured in GWh per year for large installations, such as Olympic swimming pools (SPs). In this paper, the problem is initially addressed using a phenomenological approach at steady state of the air-water coupling, based on a real case study. The aim is to identify the key phenomena and the constraints that are the most sensitive, including those related to water and air quality management. A key action lever is found in evaporation, and more specifically, water temperature and the indoor dewpoint temperature, which act as its precursors. In a second step, two different strategies were tested to reduce energy consumption for water heating. It was determined that a strategy which incorporates night setback in conjunction with a precise restart time yields a maximum gain of 4%. The second strategy aims to enhance the energy recovery of thermal solar panels by enabling slight overheating of the pool. Its large volume provides effective energy storage, with estimated energy savings of up to 17% for a 1___ C overheating. This strategy appears to be a viable option, as it is straightforward to implement. However, the impact of water overheating on the energy consumption of AHU still needs to be analyzed and managed.