IEA Solar Heating and Cooling Programm - NachhaltigWirtschaften.at

IEA SHC Task 38 Solar Air Conditioning and Refrigeration
Subtask A Report, Date:…
Table 2: Collector efficiency of the Chambery installation during the observation period
May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul
2009 2009 2009 2009 2009 2009 2009 2009 2010 2010 2010 2010 2010 2010 2010
23,2
%
27,7
%
30,8
%
31,2
%
20,3
%
21,2
%
11,9
%
9,7%
10,0
%
17,9
%
22,9
%
24,5
%
26,2
%
23,7
%
26,1
%
The collector efficiency is good for flat plate collectors in the summer and for the sunny
months. However in winter the efficiency goes low. It can be explained by the large amount
of days in winter that are not sunny enough to start the solar system, or not sunny enough to
keep the system working. However, for those days a solar radiation is still there even if it’s
not very high. As a consequence, the average collector efficiency is not very high.
Indeed, even in December, a few days appears with good collector efficiency, like on
08/12/2009 (see Figure 2) where the collector efficiency reaches 0,4. These days are just
not so numerous than in summer.
Figure 2: Collector efficiency of the Chamberry installation on 08/12/2009