The vindex well is a variant of the classic canadian well but it is much more practical, easy to implement, cost effective and efficient.
How the vindex well works is very simple, it is based on heat exchange between the air and the soil that at a certain depth its temperature remains almost constant all the time. So it is a passive geothermal system to moderate the temperature.
How it works
As illustrated in the figure, the outside air is sucked into the tube (due to a centrifugal fan) then it comes into the copper coil which is in direct contact with the soil at 7 meters depth where it undergoes a temperature change according to the outdoor air temperature. That is, since the soil temperature is constant at that depth (-7 m) and it is around 16°C throughout the year, if the air temperature is lower than 16°C then the air is heated, but if it is higher than 16°C then it is cooled, otherwise it remains almost unchanged.
The main feature of the vindex well is to use copper coils inserted into the soil at a depth of 7 m where the tempearture is almost constant. The space used by a vindex well is only 20 cm dimatero, then it is not necessary to dig the trenches tens of meters long and quite variable temperature from one season to another. The main feature of the vindex well is to use copper coils inserted into the soil at a depth of 7 m depth where the tempearture is almost constant. The space used by a vindex well is a circumference of 20 cm in diameter, so it is not necessary, like in the classical canadien well, to dig trenches of tens of meters long and where temperature is quite variable from one season to another.
The picture shows the two copper coils that were used in the two vindex wells in Celenza Sul Trigno - Italy (March 2015). The red arrow indicates the direction of air inlet into the coil, while the blue indicates the output direction.
the air temperature in output from the hair dryer is 62.4°C (measured with a laser ray thermometer). The air then enters into the tube and goes long the entire circuit inside the vindex well and comes out at a temperature of 19°C. So there has been a lowering of the temperature of 43.4°C. A very good result.
Vindex Well completed
Given the importance of the vindex well for passive natural air-conditioning, the content of this page will be updated with the results of new experiments.