Difference between ITC total in SAM and SSC

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Difference between ITC total in SAM and SSC


To the best of my knowledge, I'm entering data into SAM in the same way that I'm entering data into the SSC library. The results are the same until I enter an ITC value. SAM shows a federal ITC on the Cash Flows page, but SSC returns itc_fed_total as 0. Am I missing something that I should have set up for itc_fed_total to have a value?

I'm running pvwattsv1, annualoutput, and ippppa, specifying a PPA price. When the ITC amount and percentage are set to 0, all of my resulting cash flows from SSC match SAM's. When I add either an amount or percentage for federal ITC, SAM seems to notice, but my SSC results are unaffected.

Any idea what I might be missing? I've attached the SSC script for reference.

Paul Gilman

Dear Tucker,

Thank you for sending your script.

I think it contains a typo. The Federal ITC percentage input variable is itc_fed_percent. You typed itc_federal_percent.

When I changed the variable name and ran the script, it reports 11790180 for the itc_fed_total output variable.

Best regards,


Mea maxima culpa... Thank you for you for catching that, Paul. I can't tell you how many times I looked that over without noticing.

- Tucker

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