Adds faiman_rad and ross models to get_cell_temperature().

[ramaroesilva]

• Closes pvlib.pvsystem.Array.get_cell_temperature does not accept ross and faiman_rad models #2625
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Differently from what was originally discussed with @cwhanse and @echedey-ls, I decided not to include a verification on whether both k and noct are provided within get_cell_temperature. imo, this type of verification should be (and is) done within the temperature.ross function itself and we see that the opposite situation - expected parameters not being provided - is never verified within get_cell_temperature as I imagine it is done within each temperature model function.

@cwhanse about wind and ross model, if that's okay I still included a small note in the wind_speed description to alert ross users that providing a None is enough.

[ramaroesilva]

Have included tests for the added temperature models.

@adriesse, for the faiman_rad case could you suggest one set of example ir_down/u0/y1 values for testing? I'm asking this because of this note on the faiman_rad docstring:

When only irradiance, air temperature and wind speed inputs are provided (ir_down is None) this function calculates the same device temperature as the original faiman model. When down-welling long-wave radiation data are provided as well (ir_down is not None) the default u0 and u1 values from the original model should not be used because a portion of the radiative losses would be double-counted.

Afterwards, I can get the expected output by running pvlib.temperature.faiman_rad for poa_global=1000, temp_air=25, wind_speed=1, and your recommended parameter values.

[adriesse]

Have included tests for the added temperature models.

@adriesse, for the faiman_rad case could you suggest one set of example ir_down/u0/y1 values for testing? I'm asking this because of this note on the faiman_rad docstring:

When only irradiance, air temperature and wind speed inputs are provided (ir_down is None) this function calculates the same device temperature as the original faiman model. When down-welling long-wave radiation data are provided as well (ir_down is not None) the default u0 and u1 values from the original model should not be used because a portion of the radiative losses would be double-counted.

Afterwards, I can get the expected output by running pvlib.temperature.faiman_rad for poa_global=1000, temp_air=25, wind_speed=1, and your recommended parameter values.

For the test it doesn't really matter what the values are, and what you've done seems fine. Not sure if you want to keep ir_down a scalar as discussed above. In practice the reduction in U values will depend on the ir_down conditions at the location.

[cwhanse]

@ramaroesilva this fell off my radar, sorry. I don't have an opinion about the ross wind_speed accommodation. The if structure is OK with me, it's easy for a functools novice to understand :)

[cwhanse]

@adriesse @kandersolar nudging you if you wanted to look at this lingering PR again.

[kandersolar]

A few final comments.

[adriesse]

@adriesse @kandersolar nudging you if you wanted to look at this lingering PR again.

I'm not familiar with the PVSystem class.

[cwhanse]

@kandersolar @echedey-ls please take at look at this clean up

[kandersolar]

Let's name the parameter longwave_down instead of ir_down, towards #2653

[cwhanse]

ugh - something about end of line characters and now every line in pvsystem.py is marked as changed. Reverting, I'll replace ir_down with longwave_down manually.

[cwhanse]

@kandersolar replacing ir_down with longwave_down is a breaking change for temperature.faiman_rad. Was that intentional?

[echedey-ls]

Just a minor nitpick down below. Super PR!

[echedey-ls]

For future PRs, we will try to use superscripts instead (that would require other consistency changes in this file, it would be scope creep for this PR). Just letting you know in case you may want to pursue it.
#2205 & #2519

[cwhanse]

thanks @ramaroesilva !