The underground temperature stays far more stable than surface conditions, so by channeling air below ground into a home, summer cooling and winter heating can be enhanced. Depending on the situation, energy use can be significantly lowered or even entirely avoided for these purposes. Geothermal air conditioning offers a viable alternative in the face of winter energy shortages, and it remains an eco-friendly and inexpensive option.
Canadian wells, sometimes called Provence, represent a form of geothermal air conditioning that is growing in popularity thanks to its straightforward setup.
These systems involve pipes laid beneath and connected to the residence to regulate indoor temperatures. Because the system does not draw electricity directly, the initial installation is the main cost; thereafter, air conditioning or heating expenses drop substantially, leading to noticeable savings on utility bills.
Typical temperature differences in a Canadian well during winter show how the system can balance indoor climate with minimal energy input when used in homes.
In summer, the underground environment remains cooler, enabling the air circulated through the ducts to lower indoor temperatures more efficiently than surface air alone. This seasonal behavior helps maintain comfort while reducing the need for conventional cooling systems.
The core idea behind Canadian wells is straightforward: air collected in underground channels tends to be cooler than the house air in summer and warmer than the house air in winter. This natural temperature exchange provides a passive heating or cooling effect without relying on electricity.
Adopting this bioclimatic strategy can markedly increase a building’s energy efficiency. If the installation occurs during initial construction, costs are typically lower, but the advantages remain evident whether the system is added later or built in from the start.
The surface temperature difference remains constant with depth, and at a depth of two to three meters the underground environment often stays around 18ºC to 24ºC. This range is conducive to comfortable indoor living and reduces the demands on heating and cooling systems.
Canadian wells involve laying channels about 2 to 4 meters deep and up to 35 meters long, through which air is circulated. As air moves through these ducts, it gains the thermal influence of the surrounding soil, helping to temper it before it enters living spaces, with or without additional warmth.
It is estimated that a stable subterranean temperature exists around 15 to 20 meters deep, with shallower depths offering temperatures close to ideal indoor comfort ranges of 18º to 24ºC. This concept supports energy-efficient climate control throughout the year.
It is recommended to examine the soil beforehand.
Before installing a Canadian well, soil is assessed to determine its thermal conductivity and other properties. This helps reveal the full potential of the site and any possible drawbacks.
Soil thermal conductivity depends on porosity and saturation. Granular soils with clay or silt typically exhibit higher conductivity than sandy soils. Clean sandy soils are less conductive when dry but improve significantly when saturated. The presence of water strongly influences thermal properties, including conductivity and heat capacity.
In winter:
During winter, ambient air is cold, but at two to three meters depth the temperature stays warmer than outside. As outside air travels through underground pipes, it warms, improving indoor climate. Electric heating can be greatly reduced or even avoided, depending on the situation.
In summer:
In summer, surface temperatures rise while the underground remains cooler. Air passing through the underground pipes is cooled and enters the home a few degrees cooler, increasing comfort and lowering or eliminating the need for air conditioning or ventilation.
Reference material discusses methods for constructing a Canadian well and its practical considerations. The approach highlights the value of passive climate control and how it integrates into modern homes without heavy energy use. The aims are to provide reliable comfort while supporting sustainable energy choices. These ideas are supported by practical guides that describe soil assessment, channel dimensions, and the way soil thermal properties affect performance.
The broader takeaway is that underground air management can offer a steady, low-energy path to maintain comfortable living conditions throughout the year, complementing or replacing conventional heating and cooling solutions in suitable climates.