Earthtubes
Cooling solutions - replace your AC and supplement your winter heating. No SolarShip required!

Earth tubes are underground heat exchangers that can capture heat from and/or dissipate heat to the ground. They use the Earth's near constant subterranean temperature to warm or cool air. The tubes are double walled, and buried two metres below the ground's surface. They also provide the added benefit of controlled, filtered, temperate fresh air intake, which is especially valuable in tight, well-weatherized, efficient building envelopes.