european journal of social sciences issn: 1450-2267 - EuroJournals

European Journal of Social Sciences – Volume 5, Number 3 (2007)
Figure 4: Comparisons of the collector with and without CPC, and combined efficiency at 700 W/m 2 and Ti =
30 Cº
Combined Efficiency ( % )
70
60
50
40
30
20
10
With CPC
Without CPC
0
0 0.02 0.04 0.06 0.08 0.1
Mass flow rate ( kg/s )
The experimental results show that when the collector is operating at high mass flow rate; the
efficiencies (photovoltaic, thermal, and combined pv/t) were increase as shown in figure 5. It can see
that the combined pv/t efficiency is decrease at low flow rate because the mean photovoltaic
temperature is high. Therefore, cooling of the photovoltaic cells by increasing the mass flow rate will
increase the combined photovoltaic thermal efficiency. This is expected when the photovoltaic panel is
cooled by the incoming air.
Figure 5: The Effect of mass flow rate on efficiencies with and without CPC at 700 W/m 2 and Ti=30 Cº
Efficienciey ( % )
Pv Efficiency With CPC Pv Efficiency Without CPC
Thermal Efficiency With CPC Thermal Efficiency Without CPC
Combined Efficiency With CPC Combined Efficiency Without CPC
70
60
50
40
30
20
10
0
0 0.02 0.04 0.06 0.08 0.1
Mass flow rate ( kg/s )
Conclusion
Performance curves of the single pass, double duct solar collector with and without CPC and fins have
been obtained. The experimental results were shown. On the basis of the comparisons made it can be
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