The HEAHP consortium has produced a pre-commercial air-to-water reversible heat pump prototype working with propane for use in the mild climate conditions typical of Southern Europe. With respect to our previous commercial R22 reference machine, this prototype works safely, with a much lower charge (66%), a similar or even higher capacity and much better efficiency (increase of 10% to 20%). All the aimed improvements included in the milestones (40% lower charge, similar capacity, 10% better efficiency) were clearly surpassed.
The obtained results have been possible not only because of the excellent properties of the refrigerant, but also because of the intense combined experimental and computational effort of the consortium to adapt heat pump technology and designs to propane.
Specific results:
Methodology for characterisation of reversible air-to-water heat pumps:
-Development of a new energy-saving methodology for measuring heating and cooling capacities of Heat Pumps.
Global model of an air-to-water reversible heat pump unit working with propane. Software and documentation:
-Development of a very precise Heat Pump model incorporating very accurate sub-models for each Heat Pump component. It is also provided with a Graphic User Interface.
Heat exchangers calculation program:
-Development of program for Heat Exchangers simulation allowing, through a Graphic User Interface, the study of different geometries and flow configurations.
-Programme for calculation of the performance of volumetric compressor.
-This program simulates any type of piston compressor. It has the possibility to choose the circulating refrigerant in a database. The simulation gives pressure and temperatures of the refrigerant in all points, the movement of the walls and the circulating mass flow rate.