Geothermal heat pumps are a promising technology for heating and cooling systems in buildings and they have been diffusing all over the world. The paper deals with an innovative layout for geothermal systems: the proposed design features a heat-storage water tank, buried just below the ground level, that acts as a thermal flywheel, decoupling the utility side (i.e. the heat-pump) from the geothermal side (i.e. the boreholes). This innovative approach could allow a significant reduction of the geothermal unit, hence requiring for fewer and/or shorter boreholes (up to 60-70%) while still providing for the total energy need. The power peaks are covered by the water in the tank, while the reduced-size geothermal unit is used with a higher duty cycle and it still provides for the whole energy need. A pilot system, co-funded by of the Italian Ministry for the Environment within the SCER project (Development of a new renewableenergy conditioning system for commercial buildings), has been designed, implemented, and tested near the city of Perugia, Italy. The system has been dimensioned on the results of the building energy-demand simulation and the occupancy schedule. The design of the heat-storage tank, the heat exchangers, the monitoring system, and the operation modes were carefully studied. The system performance is monitored with a custom data acquisition system. First results of both winter heating and summer cooling monitoring are presented.
An innovative geothermal heat-pump system including a heat-storage water tank: development and experimental results.
COTANA, Franco;MORETTI, ELISA;BONAMENTE, EMANUELE;PETROZZI, ALESSANDRO
2013
Abstract
Geothermal heat pumps are a promising technology for heating and cooling systems in buildings and they have been diffusing all over the world. The paper deals with an innovative layout for geothermal systems: the proposed design features a heat-storage water tank, buried just below the ground level, that acts as a thermal flywheel, decoupling the utility side (i.e. the heat-pump) from the geothermal side (i.e. the boreholes). This innovative approach could allow a significant reduction of the geothermal unit, hence requiring for fewer and/or shorter boreholes (up to 60-70%) while still providing for the total energy need. The power peaks are covered by the water in the tank, while the reduced-size geothermal unit is used with a higher duty cycle and it still provides for the whole energy need. A pilot system, co-funded by of the Italian Ministry for the Environment within the SCER project (Development of a new renewableenergy conditioning system for commercial buildings), has been designed, implemented, and tested near the city of Perugia, Italy. The system has been dimensioned on the results of the building energy-demand simulation and the occupancy schedule. The design of the heat-storage tank, the heat exchangers, the monitoring system, and the operation modes were carefully studied. The system performance is monitored with a custom data acquisition system. First results of both winter heating and summer cooling monitoring are presented.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
