SAM 2013.1.15 versus previous versions

  • sidom
  • Topic Author
More
11 Feb 2013 10:56 #1267 by sidom
SAM 2013.1.15 versus previous versions was created by sidom
Hello Paul,

I am trying the Empirical model of the last version (2013.1.15). There are great differences between the output results of this version and previous versions. Which are the main modifications implemented in this last version that affects the results (clearly lower)?

Thanks and regards

Please Log in or Create an account to join the conversation.

  • Paul Gilman
More
11 Feb 2013 22:26 #1268 by Paul Gilman
Replied by Paul Gilman on topic SAM 2013.1.15 versus previous versions
Hello,

The SAM release notes (available from SAM's Help menu) list changes between versions and describe their impact on results. In SAM 2013.1.15, we fixed a bug in the empirical trough model that affected solar field calculations and resulted in the model over-predicting the annual output by about 4%. The current version should be more accurate than older versions.

Best regards,
Paul.

Please Log in or Create an account to join the conversation.

  • sidom
  • Topic Author
More
07 Oct 2013 16:33 #1269 by sidom
Replied by sidom on topic SAM 2013.1.15 versus previous versions
Hello Paul,

Back to question made some months ago, could you please be more accurate about the changes implemented in the 2013 version? The bug fixed in empirical trough model is related to the solar field warm up or solar field losses calculations?

Thanks in advance

Please Log in or Create an account to join the conversation.

  • Paul Gilman
More
16 Oct 2013 17:28 #1270 by Paul Gilman
Replied by Paul Gilman on topic SAM 2013.1.15 versus previous versions
Hello,

The empirical trough model issue that we fixed in SAM 2013.1.15 is a little complicated to explain:

The empirical trough model uses an iterative algorithm to calculate the startup energy required at the start of each day. The error involved the value used in the iteration for the system's average temperature in the time step before start-up, which should have been fixed at the system's average temperature in that time step, but instead was allowed to fluctuate and tended to follow the iterated system temperature value in the current time step. This error caused the startup energy value to be significantly lower than it should have been.

Best regards,
Paul.

Please Log in or Create an account to join the conversation.

Moderators: Paul Gilman
Powered by Kunena Forum

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

NREL Home

NREL Research

Follow NREL

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.