IIR document

Energy saving potential of capacity controlled brine-to-water heat pumps.

Author(s) : KARLSSON F., FAHLÉN P.


Variable-speed capacity controlled heat pumps have in many previous investigations proved to be more energy efficient than single-speed on/off controlled units. These investigations have mainly considered air-source heat pumps. This study investigated the effects of applying variable-speed capacity control to brine-to-water heat pumps, which is the most common type of heat pump in Sweden nowadays. The investigation was made both by laboratory tests and by calculations of the seasonal performance factor comparing variable-speed control and on/off control. The laboratory tests showed a somewhat surprising result; the variable-speed control was less efficient than the on/off control. An analysis of test data indicated a need for development of hermetic variable-speed compressors suitable for the present kind of heat pump. Furthermore, the theoretical investigation indicated that by applying suitable variable-speed control to brine-to-water heat pumps the energy efficiency can be increased by approximately 10% compared with conventional single-speed units.

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  • Original title: Energy saving potential of capacity controlled brine-to-water heat pumps.
  • Record ID : 2004-2480
  • Languages: English
  • Source: 21st IIR International Congress of Refrigeration: Serving the Needs of Mankind.
  • Publication date: 2003/08/17


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