Geothermal system using single water supply system for heating and cooling smart farm and building, and method for constructing geothermal system

A method of constructing a geothermal system, the method comprising:

• a first step of constructing two or more geothermal holes underground;
• a second step of constructing a water collection and supply well on the ground or underground so as to be adjacent to the two or more geothermal holes;
• a third step of connecting the two or more geothermal holes and the water collection and supply well to each other via a water return and circulation pipe such that underground water in the two or more geothermal holes is collected in the water collection and supply well;
• a fourth step of installing a heat pump and providing a pipe between the heat pump and the water collection and supply well such that the underground water collected in the water collection and supply well is circulated to the heat pump;
• a fifth step of installing a supply pipe such that the underground water that has passed through the heat pump is supplied to the two or more geothermal holes,
• wherein the supply pipe comprises:
• a ground-side supply portion configured to guide the underground water that has passed through the at least one heat pump;
• a geothermal-hole-side supply portion connected to the ground-side supply portion, the geothermal-hole-side supply portion being provided in each of the two or more geothermal holes, the geothermal-hole-side supply portion being configured to guide the underground water to a bottom of each of the two or more geothermal holes;
• and
• a water return portion connected to the geothermal-hole-side supply portion, the water return portion being configured to discharge the underground water into each of the two or more geothermal holes while guiding the underground water upwards.