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
liter fresh water have been consumed this corresponds to 70 l fresh water per hour of
full load operation. The open wet cooling tower did supply cooling water temperatures
below 20°C a couple of days, e.g. the direct use of this cooling water for the chilled
ceiling circuit is technically reasonable.
- The solar thermal system - composed of 40.50 m² flat-plate collectors and 2000 liter
stratifying hot water tank - generates sufficient driving temperatures for the absorption
chiller. Typically the driving temperature starts with 75°C and decreases to 55°C. The
low flow operation strategy for the flat-plate collectors in the rage below 20 l/h m²
supplies sufficient driving temperatures.
System reliability and overall success of the installation
The monitoring system did operate reliably. Some measurement data logging gaps appeared
because of reboot troubles of the data logging system in case of temporary grid blackouts.
The measurement signals of the pyranometer did not deliver reasonable values and the
technical problem could not be solved on site.
During the monitoring period once the absorption chiller produced too low cold water
temperatures which led to crystallization phenomena of the working fluid. The manufacturer
did maintenance work which means mainly refilling of lithium-bromide and recreation of
vacuum.
Office room air temperatures were measured as well and during the monitoring period and
only some few hot days were identified with office room air temperatures exceeding 26°C.
Consequently the thermal user comfort lead to a high acceptance of the office users.
Photos
Office building of SOLution headquarters
Sattledt/ Austria
Technical room equipped with EAW
WEGRACAL SE 15 absorption chiller, hot
and cold water storage tank
Chilled ceiling device
Wet open cooling tower
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