THE CASE OF A GEOTHERMAL HEAT PUMP SYSTEM WITH A COMPACT GROUND HEAT EXCHANGER IN DRY SOIL AND SOLAR PANELS RECHARGING

Abstract: In the near future, in the ground source heat pumps industry compact ground heat exchangers will probably be an answer in case of small gardens, without expensive drilling of boreholes. Solar recharging of ground loops is today a field of research in the geothermal heat pumps industry. This article illustrates the case history of a 10kW geothermal heat pump system installed in 2004 in the north west of Italy, with a soil-water heat pump and compact ground collectors, in the first time connected to a heat recovery from exhaust air unit. One of the main technical bottlenecks was the fact that the soil is locally very dry and low rainfall levels characterize the area during winter. In autumn 2006 the system was connected to solar panels for hot water production and ground loop recharging. Main parameters were recorded and they allow now a first analysis of the possible performances obtained from solar ground loop recharging. Key Words: compact ground heat exchanger, ground source heat pumps, geothermal heat pumps, ground solar rechargin