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kandersolarcwhanseRDaxiniadriesseIoannisSifnaios
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Add guidance about temperature modeling to User Guide (#2591)
* create temperature user guide page * Apply suggestions from code review Co-authored-by: Cliff Hansen <[email protected]> * Apply suggestions from code review Co-authored-by: RDaxini <[email protected]> * add mention of parameter conversion with GenericLinearModel * add note about IR * move "other functions" up to below the table * fix spelling * Apply suggestions from code review Co-authored-by: Anton Driesse <[email protected]> * feedback from review Co-Authored-By: Ioannis Sifnaios <[email protected]> * more changes from review * Update docs/sphinx/source/user_guide/modeling_topics/temperature.rst * Update docs/sphinx/source/user_guide/modeling_topics/temperature.rst Co-authored-by: Echedey Luis <[email protected]> * split paragraph --------- Co-authored-by: Cliff Hansen <[email protected]> Co-authored-by: RDaxini <[email protected]> Co-authored-by: Anton Driesse <[email protected]> Co-authored-by: Ioannis Sifnaios <[email protected]> Co-authored-by: Echedey Luis <[email protected]>
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‎docs/sphinx/source/user_guide/index.rst‎

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@@ -26,6 +26,7 @@ This user guide is an overview and explains some of the key features of pvlib.
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modeling_topics/clearsky
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modeling_topics/weather_data
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modeling_topics/singlediode
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modeling_topics/temperature
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.. toctree::
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:maxdepth: 2

‎docs/sphinx/source/user_guide/modeling_topics/temperature.rst‎

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.. _temperature:
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Temperature models
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==================
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pvlib provides a variety of models for predicting the operating temperature
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of a PV module from irradiance and weather inputs. These models range from
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simple empirical equations requiring just a few multiplications to more complex
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thermal balance models with numerical integration.
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Types of models
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---------------
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Temperature models predict one of two quantities:
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- *module temperature*: the temperature as measured at the back surface
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of a PV module. Easy to measure, but usually marginally less
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than the cell temperature which determines efficiency.
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- *cell temperature*: the temperature of the PV cell itself. The relevant
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temperature for PV modeling, but almost never measured directly.
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Temperature models estimate these quantities using inputs like incident
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irradiance, ambient temperature, and wind speed. Each model also takes
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a set of parameter values that represent how a PV module responds to
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those inputs.
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Parameter values generally depend on both the PV
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module technologies, the mounting configuration of the module,
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and on any weather parameters that are not included in the model.
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Note that, despite models conventionally being associated with either
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cell or module temperature, it is actually the parameter values that determine
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which of the two temperatures are predicted, as they will produce the same
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type of temperature from which they were originally derived.
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Another aspect of temperature models is whether they account for
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the thermal inertia of a PV module. Temperature models are either:
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- *steady-state*: the module is assumed to have been at the specified operating
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conditions for a sufficiently long time for its temperature to reach
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equilibrium.
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- *transient*: the module's thermal inertia is included in the model,
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causing a lag in modeled temperature change following changes in the inputs.
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Other effects that temperature models may consider include the
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photoconversion efficiency and radiative cooling.
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The temperature models currently available in pvlib are summarized in the
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following table:
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+----------------------------------------------+--------+------------+---------------------------------------------------------------------------+
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| Model | Type | Transient? | Weather inputs |
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| | | +----------------+---------------------+------------+-----------------------+
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| | | | POA irradiance | Ambient temperature | Wind speed | Downwelling IR [#f1]_ |
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+==============================================+========+============+================+=====================+============+=======================+
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| :py:func:`~pvlib.temperature.faiman` | either | | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.faiman_rad` | either | | ✓ | ✓ | ✓ | ✓ |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.fuentes` | either | ✓ | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.generic_linear` | either | | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.noct_sam` | cell | | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.pvsyst_cell` | cell | | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.ross` | cell | | ✓ | ✓ | | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.sapm_cell` | cell | | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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| :py:func:`~pvlib.temperature.sapm_module` | module | | ✓ | ✓ | ✓ | |
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+----------------------------------------------+--------+------------+----------------+---------------------+------------+-----------------------+
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.. [#f1] Downwelling infrared radiation.
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In addition to the core models above, pvlib provides several other functions
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for temperature modeling:
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- :py:func:`~pvlib.temperature.prilliman`: an "add-on" model that reprocesses
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the output of a steady-state model to apply transient effects.
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- :py:func:`~pvlib.temperature.sapm_cell_from_module`: a model for
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estimating cell temperature from module temperature.
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Model parameters
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----------------
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Some temperature model functions provide default values for their parameters,
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and several additional sets of temperature model parameter values are
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available in :py:data:`pvlib.temperature.TEMPERATURE_MODEL_PARAMETERS`.
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However, these generic values may not be suitable for all modules and mounting
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configurations. It should be noted that using the default parameter values for each
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model generally leads to different modules temperature predictions. This alone
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does not mean one model is better than another; it's just evidence that the measurements
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used to derive the default parameter values were taken on different PV systems in different
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locations under different conditions.
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Parameter values for one model (e.g. ``u0``, ``u1`` for :py:func:`~pvlib.temperature.faiman`)
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can be converted to another model (e.g. ``u_c``, ``u_v`` for :py:func:`~pvlib.temperature.pvsyst_cell`)
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using :py:class:`~pvlib.temperature.GenericLinearModel`.
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Module-specific values can be obtained via testing, for example following
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the IEC 61853-2 standard for the Faiman model; however, such values still do not capture
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the dependency of temperature on system design and other variables.
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Currently, pvlib provides no functionality for fitting parameter values
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using measured temperature.

‎docs/sphinx/source/whatsnew/v0.13.2.rst‎

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Documentation
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~~~~~~~~~~~~~
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* Provide an overview of single-diode modeling functionality in :ref:`singlediode`. (:pull:`2565`)
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* Provide an overview of temperature modeling functionality in :ref:`temperature`. (:pull:`2591`)
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* Fix typo in parameter name ``atmos_refract`` in :py:func:`pvlib.solarposition.spa_python`
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and :py:func:`pvlib.spa.solar_position`. (:issue:`2532`, :pull:`2592`)
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