IEA Solar Heating and Cooling Programm - NachhaltigWirtschaften.at

IEA SHC Task 38 Solar Air Conditioning and Refrigeration Subtask A Report A-D3b, Date: December 2010
Configuration
Heat storage
Cold storage
Auxiliary heater
Use of auxiliary heating system
Auxiliary chiller
System scheme
2 m 3 water
none
Institute heat network, operated by CHP and gas boiler
Auxiliary driving source for chiller, auxiliary driving source
for heat pump operation in winter
no
System performance
For one year of operation (August 2008 until July 2009) an average seasonal Coefficient of
Performance of COP = 0.43 was observed. The solar thermal coverage of the total heat input
for cooling was around 45% while for heating it was 6.7%. It has to be remarked that the
solar energy in winter is only used to drive the adsorption heat pump if it reaches 70°C and is
not used directly for heating. The chiller was newly evacuated before the monitoring period.
During winter, the machine runs in heat pump mode; the resulting COP in this operation
mode for the whole heating season was 1.25.
In summer 2009 the adsorption chiller ACS05 was exchanged by the model ACS08, which
started its operation in November 2009. In the heating season 2009/2010 (Sept. 2009-May
2010) a thermal COP of 1.27 was achieved while the solar fraction in the driving heat was
3.2%. This means that 3.2% of the driving heat was provided by the solar system. The
summer period 2010 (April – Sept. 2010) a cooling COP of 0.58 and a solar fraction of 65.2%
was obtained.
It has to be mentioned that the systems was operated every day from around 8 to 17 o’clock
whenever the temperatures in the supply air were above 20°C (Cooling mode) and below
14.5°C (heating mode). Solar energy was used if the temperature in the upper part of the
storage was above 73°C. Further, it has to be mentioned that the driving temperatures from
the CHP driven network were very irregular and often in the range between 55 and 70°C.
System reliability and overall success of the installation
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