Étude comparative de la performance énergétique de deux salles (A16 & A17) en contexte de rénovation: impact de l'isolation des niches de radiateurs et de la réparation des fenêtres de la salle A17 sur les déperditions/consommation énergétique

Abstract

This thesis presents a comparative study of the energy performance of two rooms, A16 and A17, in Block A of the central building on the Kirchberg campus of the University of Luxembourg, in view of renovation. The main goal was performing in-situ measurements, such as the blower door test and the decay method to evaluate the airtightness of the envelope, comfort, and effectiveness of insulating the radiator niches and purely aluminum parts of Room A17 regarding heat losses and energy needs. Moreover, it was identified as an improvement in energy performance that would ensure optimum comfort. The results obtained after the first phase, Case Study 1, show that the room loses an astonishing amount of energy through its envelope, tending to 9,712 kWh/year: 8,330 kWh due to transmission losses (walls and windows) and 1,382 kWh due to ventilation losses for a heating period of 200 days (4,800 hours). Infiltration of 0.26 h⁻¹ was measured by using the tracer gas decay method. Results after renovation showed that the infiltration rate increased to n = 0.15 h⁻¹ and different heat losses. Losses decreased by 32.16 % at 3,124 kWh out of which 2,539.38 kWh was due to reduced transmission losses and 585 kWh because of ventilation losses. Since the heating period is the same, the calculated annual losses are 6,588 kWh/year. This also results, thanks to the renovation works, in a 32% reduction in emissions from the energy mix, amounting to 108.32 kgCO2e for biomass (pellets) and 88.37 kgCO2e for natural gas. Replacing the current single-glazed windows with double-glazed or even triple-glazed windows during future renovations should reduce transmission losses in the windows. This would again reduce the energy required in heating.