This technique uses vertical drilling to capture geothermal energy for heating with a minimal surface area. Sensors made of polyethylene tubing are inserted into wells spaced 5-10 meters apart near or under a house. The wells are then sealed with a gravel/sand and bentonite mixture to conduct heat and protect against landslides. A water/glycol mixture circulates through the closed system of sensors to extract heat from the natural underground temperature of 10°C. A standard water/water heat pump is used along with a floor heating or low-temperature central heating system inside, providing excellent performance coefficients of 4 or more due to the constant underground temperature.