How to input measured weather data through SAM?

Hello,
I'm seeking some help on how to approach running a custom 15-minute weather data file within SAM.
 
Ultimately I would like to input my daily measured 15-minute weather data obtained from an PV plant to determine inverter production, or if possible string output values. I tried to run a single day of 15 minutes measured data through SAM, however it requires inputs for an entire year, is there a way around this?
 
I've tried searching around the forums, but haven't had much luck. Or in some cases the links were expired to examples. Thank you in advance for your help!

Hi JRR,

If you have solar resource and meteorological data for an entire year, you can create your own SAM CSV file using the format description listed here: sam.nrel.gov/weather-data/weather-data-publications.html .

If you only have some data for the entire year, for example irradiance data but no meteorological data, you could download a weather file from the NSRDB (using the tools on SAM's Location and Resource page) and then edit the file to replace columns of NSRDB data with your measured data.

You can also add a column with the heading "POA" to use measured irradiance data from the plant in place of the solar irradiance (DNI, DHI) data. The weather file can contain a POA column in addition to the DNI, DHI and/or GHI columns. You choose what data SAM uses for the simulation using the options on the Location and Resource page under "Advanced" at the bottom of the page.

If you just have data for a few hours or days, you could modify a weather file from the NSRDB by replacing the data for those hours or days with your data, placing the data in the correct rows of the weather file so the time stamps match the data. You would then ignore the simulation results for time steps other than those of interest.

One other option if you are writing code to interact with the SSC API using tools in the SAM Software Development Kit, or using PySAM with Python, there is a new option as of SAM 2020.2.29 to run a simulation for individual time steps (as long as your model does not include battery storage). You can read about how that works here, github.com/NREL/ssc/pull/418 . Let me know if you would like to pursue that option.

Best regards,
Paul.

Hello,

can I import data file and run simulation without having some data available (wind direction, snow depth), and if yes which data are obligatory to have and which not?

Hi Ivan,

See my reply to your other post:

sam.nrel.gov/forum/forum-general/4063

Best regards,
Paul.