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<p class=MsoNormal><font size=1 face=Arial><span lang=EN-GB style='font-size:
8.0pt;font-family:Arial'>Dear TRNSYS group,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-GB style='font-size:
8.0pt;font-family:Arial'>I am trying to model a solar hot water system using
vacuum tubes with concentrator (I am using Schott vacuum tubes). I only have
the instant efficiency test (quadratic equation) from the manufacturer. I am
not sure if I should use TYPE 74 (CPC collector) or TYPE 71 (Vacuum Tube),
because I don’t know if Type 71 –or the instant efficiency
equation- will take account of the “concentration effect” into the
absorber. Does anyone have any recommendations on what to do? Many thanks<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-GB style='font-size:
8.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p><font size=1 face=Arial><span style='font-size:8.0pt;font-family:Arial'>Xavi
Ariņo<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-GB
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=ISOCPEUR><span lang=EN-GB
style='font-size:10.0pt;font-family:ISOCPEUR'><o:p> </o:p></span></font></p>
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