During the summer, the sun warms the ground and heat is stored in the soil. This heat is collected by burying plastic pipes just 1 metre under the surface with each length at least 1 metre apart. An environmentally-friendly nonfreezing solution is circulated in the piping, collects this heat and transports it to the heat pump.

Typically the length of collector pipe required is between 200 and 600 metres depending on the heat demand and size of heat pump installed.
The surface ground collector method is cost effective where sufficient useable land is available. The higher the water content of the soil the better.