PV efficiency error

  • Juan Peña
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24 Nov 2011 09:51 #39 by Juan Peña
PV efficiency error was created by Juan Peña
Hi all, Just noticed that in a PV simulation (at least for CEC model) the values of the module efficiency returned by SAM are expressed in 1/10 (not in 1/100 or % as is claimed). The calculations made after seem to be correct.
This is true for the version 2011,6,30.
greetings!

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  • Paul Gilman
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28 Nov 2011 19:10 #40 by Paul Gilman
Replied by Paul Gilman on topic PV efficiency error
Dear Juan,

Thank you for the message.

The hourly module efficiency values that SAM reports in the data tables on the Results page appear correct. For example, for the first 24 hours of the simulation (January 1) they in the range of roughly 7% to 14% for the Canadian Solar CS6P-225PX, using default values for all inputs except the module.

Did you see different values?

Best regards,
Paul.

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  • Juan Peña
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06 Dec 2011 11:38 #41 by Juan Peña
Replied by Juan Peña on topic PV efficiency error
Ok I checked what you tell me, and it is working fine. But see:

I made a new model with the same characteristics, same location, it gives the same output.
but when I take a look to the module efficiency, I get for both files:

Module Eff. (%), Hourly

0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
8.9845 0.89845
15.0104 1.50104
15.5409 1.55409
15.0518 1.50518
14.5146 1.45146
14.4907 1.44907
14.6116 1.46116
14.9371 1.49371
14.9883 1.49883
13.1681 1.31681
8.21877 0.821877
0 0
0 0

It seems it is not possible to upload files here, right?
If you want I can send you the file to an address. Just for your interest, since it really does not represent an impact in the results.

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  • Juan Peña
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06 Dec 2011 11:58 #42 by Juan Peña
Replied by Juan Peña on topic PV efficiency error
I constructed the same model in the same version with same characteristics and location and this is what I get when I compare the two model´s module´s eff:

(data taken from hourly tables in SAM)
Module Eff. (%), Hourly
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
8.9845 0.89845
15.0104 1.50104
15.5409 1.55409
15.0518 1.50518
14.5146 1.45146
14.4907 1.44907
14.6116 1.46116
14.9371 1.49371
14.9883 1.49883
13.1681 1.31681
8.21877 0.821877
0 0
0 0

Strange. The numbers are the same but divided by ten.
(This is not affecting results like energy output, etc)

Since it seems not possible to attach documents when replying , if you want to take a look to the file just say me an address and I will send it to you.

Juan Peña

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  • Juan Peña
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06 Dec 2011 12:03 #43 by Juan Peña
Replied by Juan Peña on topic PV efficiency error
I checked out what you told me. It is right.
I constructed my model another time and I have got good values, comparing with the previous ones:

Module Eff. (%), Hourly
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
8.9845 0.89845
15.0104 1.50104
15.5409 1.55409
15.0518 1.50518
14.5146 1.45146
14.4907 1.44907
14.6116 1.46116
14.9371 1.49371
14.9883 1.49883
13.1681 1.31681
8.21877 0.821877
0 0
0 0


Strange. The numbers are the same but divided by ten.
(This is not affecting results like energy output, etc)


Juan Peña

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  • Paul Gilman
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09 Dec 2011 19:21 #44 by Paul Gilman
Replied by Paul Gilman on topic PV efficiency error
Dear Juan,

It is not clear to me where the values in the second column of your table come from. Are those values for a case using a different PV module?

I am working with the website administrator to allow file attachments to forum posts and comments. Sorry for the inconvenience.

Best regards,
Paul.

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