Tilt equal to Latitude

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Tom Hardy
Tilt equal to Latitude

Instead of the per default way of specifying the value of the tilt for a certain location as in https://nsrdb.nrel.gov/api-instructions:
# Set tilt of system in degrees
ssc.data_set_number(dat, 'tilt', 25)

I would like to automatically assign to the value of the tilt, the value of the latitude for each location. The sam-sdk-2016-3-14-r3 / ssc_guide.pdf (page 39) specifies than, for Python, it should be written like:
ssc.data_set_number(dat, 'tilt_eq_lat', 1)

Yet, when including the former line in this example (https://nsrdb.nrel.gov/api-instructions), it gives an error:

--> df['generation'] = np.array(ssc.data_get_array(dat, 'gen'))
ValueError: Length of values does not match length of index

Should it be specified, however, in another way?

Paul Gilman

Dear Tom,

The example in the SSC Guide is based on the pvwattsv1 compute module. For the pvwattsv5 module, the input variable tilt_eq_lat is not available. You can use the SDKtool Module Browser to explore the variables of the different compute modules.

If you want to set the tilt angle equal to the latitude value from the weather file, you can do that in your Python code by reading the latitude value from the weather file, and then setting the value of the tilt variable to that value.

Best regards,

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