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
Typical operation temperature
Configuration
Heat storage
Cold storage
Auxiliary heater
Use of auxiliary heating system
Auxiliary chiller
92 °C driving temperature for chiller operation
2x1 m³ water tank (serial) and 1,6 m³ latent heat storage
No
Pellet boiler
Yes
Well
System scheme
System performance
The system has been in operation and monitored for three complete years (2008-2010). Due
to the low system temperatures for heating and moderate chilled water temperatures
supplied to the activated ceilings in summer a high collector yield of 400 kWh / (m² a) is
obtained.
The absorption chiller itself has been operated for about 600 hours a year, producing cold at
15 °C by means of solar heat about 90 °C with an average thermal Coefficient of
Performance of 0.69 up to 0.72. By replacing some ineffective pumps with high efficiency
components in spring 2009 the overall electrical COP increased significantly (about 20 %).
The average total electrical COP of the solar cooling system was 6.6 in 2009. Almost 60% of
the primary energy has been saved compared to a conventional compression cooling system
supplying the same amount of cold.
During the monitoring period the two latent heat storage modules have undergone over 800
loading and unloading cycles under real conditions. Due to the use of the latent heat storage
the cooling water return temperature did not exceed 33.5 °C despite dry air cooling and
ambient temperatures above 32 °C. In heating mode about 15 % of the overall heat demand
has been provided by the latent heat storage.
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