Ground source heat pumps use the earth as a source of heat energy. Heat from the ground is captured by a loop of pipes (called a heat exchanger) buried underground. This heat is then transferred to a pump inside your home which then transfers the heat to your home's radiators and hot water heater. The warmth of the earth helps heat up your home without needing to use as much electricity or gas. It's like a giant refrigerator - it pulls heat from the ground, pumps it into your home, and keeps your home nice and warm!