BuildSysPro-IAQ : Impact of Energy systems in French residential buildings on IAQ and Energy Consumption

Recent constraints on building energy consumption have led to the design and renovation of increasingly energy-efficient buildings, with a strong emphasis on renewable energies, while all too often neglecting criteria related to overall comfort (thermal, acoustic), well-being and health impacts (IAQ). This has led to the emergence of highly confined buildings as a result of more airtight envelopes and the use of ventilation equipment with very low air renewal rates, which can generate high levels of humidity and indoor air pollutant concentrations.

This article presents the results of an evaluation of the impact of different energy solutions conventionally installed in French residential homes on both IAQ and energy consumption of the building. The 0D/1D simulations were carried out using the BuildSysPro-IAQ modelica library, developed by EDF R&D (H Sayegh et al, 2023). The simulated model is the multi-zone Mozart house (a three bedrooms house), in compliance with the most recent thermal end environmental regulation in France (RE 2020).

The various energy systems considered for heating, DHW and ventilation are Joule effect heating, a thermodynamic water heater, an air-to-water heat pump for heating and DHW, and a heat pump on extracted air and water for heating and DHW. Several mechanical ventilation systems widely installed in French single-family homes, representing around 80% of the market, are considered, studied and compared. Concentration and occupational exposure to CO2, NO2, COV, PM25 and water vapor, all considered to be common household contaminants emitted as by-products of human metabolism and gas cooking, are evaluated over a year for a generic occupational schedule of four family members, consisting of a mother, a father, a son and a daughter. IAQ is assessed by means of IAQ indices.

In the literature, several authors have proposed different indices. In this study, it was decided to analyze the quality of indoor environments through 4 indices: ULR-QAI, DALY, ICONE and TAIL. The pollutant concentrations predicted by BuildSysPro-IAQ will be used to calculate the indices. The results will make it possible to compare the impact of the different energy systems studied, using these indices in conjunction with energy consumption. This study will also enable us to compare IAQ indices and their ability to assess indoor air quality.