Use of low-enthalpy geothermal resources for greenhouse heating: an experimental study

Abstract

The energy and economic performance analysis of integrated photovoltaic and geothermal systems, for greenhouse heating, was investigated in a experimental study developed at the University of Bari, Southern Italy. A 7.2 kW geothermal heat pump combined with a 120 m vertical double U-bend ground heat exchanger was installed in order to supply the thermal energy demand of 48 m2 single plastic skin greenhouse. Heat extraction energy from the soil, air temperature above the heated cultivated surface, growing media temperature, water temperature inside the heating system were measured and recorded continuously by a system composed of sensors and data logger. Results of the experiment showed that the use of geothermal sources integrated with photovoltaic panels can supply of totally heat energy demand of greenhouse with zero air emission and economy saving of 40% compared to the traditional heating systems.