Different results depending on the SAM Version 2015 or 2014 (SAM 2015.1.30 & SAM 2014.1.14 )

Hello,

I want to change my SAM-Version from the old 2014.1.14 to your new one 2015.1.30. Unfortunately it is not possible to open all the .zsam-files with the new Version.

So I tried to re-create my old SAM file with the new version. (Like your advise "you will need to re-create your SAM file(s) by hand" sam.nrel.gov/node/69196 )

It is a parabolic trough physical system. But the results are not the same. I get quite different results like annual energy 177 instead of 166 GWh. I triple checked all input parameters.
Even when I use the non-financial model.

Can you give me a hint why the results are so different?

Thank you

Tommes

Dear Tommes,
There are number of things that might be causing the difference. Please see the  release notes for a basic list of differences between versions that might help you find causes of the difference.
Please check the loss inputs to be sure they are consistent between the files. In SAM 2014.1.14 and earlier, you specify losses on the Performance Adjustment input page. The "Percent of annual output" is a percentage of the output. In SAM 2014.11.24 and later, you specify losses for the CSP models on the Power Cycle page (under "Availability and Curtailment" as a reduction in the output. For example, to specify a 4% loss, you would use 96%, and in the new version you would use 4%.
If you would like me to help you find the source of the differences, please [url=mailto:sam.support@nrel.gov?subject=SAM%20Files%20from%20Support%20Forum t=_self]email me[/url] both the .zsam and .sam files (along with the weather file if it not one that came with SAM).
Best regards,

Paul.