Geothermal system for frost protection of ground surface e.g. airport runway, has closed hydraulic circuit including fluid that is movable under effect of temperature variation outside system, where fluid is confined under pressure

摘要

The system (1) has a closed hydraulic circuit (C) including fluid (F) that is movable under the effect of temperature variation outside the system. The fluid is confined under pressure in the closed circuit, where change in temperature of portions (F12, F40) of the fluid results in variation in pressure in the closed circuit and/or phase change of the portion of the fluid. The fluid is refrigerant selected from hydroflurorocarbon (HFC), hydrofluoro-olefins (HFO), ammonia (NH3), carbon dioxide (CO2) or carbon monoxide (CO). An independent claim is also included for a method for implementation of a geothermal system for maintaining temperature of a ground surface above freezing temperature.