[EnergyPlus_Support] Low solar collector efficiencies?

["Kristin Field" <fieldkm@xxxxxxxxx>]

Has anyone else run a solar collector (thermal) system and output
hourly efficiencies?  I did this, and they were extremely low.  Based
on manufacturer data (Thermomax AST80 parameters), I would expect
efficiencies in the 50-80% range.  But my output shows more like
10-30%.  I would think that this would be independent of my loop
configuration.

One thing I wonder about is that my collector surfaces are much larger
than the test surfaces.  Each collector surface (there are 6) is about
50m^2, and the test surface is 11m^2.  I was hoping not to have to
have 30 collectors in parallel, but if that is what I need to do to
get a normal efficiency, it will be good to know that.

I will upload my .idf and .csv files (.csv has hourly collector
efficiencies for one of the collectors) shortly.

Thanks,
Kristin

P.S. My file names have "CityParkGH" and today's date in them.



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