An earth-to-air heat exchanger is a system that decreases a building heating/cooling load. It is composed of an underground pipe network in which air circulates before being injected into the building. Even if though this technology had been known for a while, it is rarely used namely because of the cost associated with excavation. Nevertheless, if the heat exchanger is placed around the foundations during their construction, this cost is vanished. However, the space available is then limited. This study tries to estimate the economic viability of this kind of configuration for a one-family house in Montréal. For this, simulations were carried out using the TRNSYS software.
A sizing study was done to find the configuration that gives the best results. It concluded that ducts with small diameters made of a cheap material are better and that they should be placed as deep and as far of the foundation as possible. The results show significant losses by thermal short-circuiting and coupling. Only around 50 % of the sensible heat exchanged with the ground is used to reduce the load. The heat exchanger in its optimal configuration reduces the heating/cooling load of the building by 711 kWh/year. This value is too low to yield a reasonable payback period for the purchase and the installation of the exchanger. This study does not indicate a great potential for this type of system in Quebec. A sensitivity study was also carried out and its conclusion are that the simulation results are strongly tied to the ground and weather parameters used.
| Date | 21 Jul 2020 |
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| Original language | French |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Daniel Rousse (Supervisor) |
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Patin, M. (Author),
Rousse (Supervisor),
21 Jul 2020Student thesis: Master's thesis › Master in Engineering: Environmental Engineering