v0.9.0.rst

v0.9.0 (September 1, 2021)

Breaking changes

• Moved functions related to inverters from pvsystem.py to inverter.py. Functions are renamed to follow a more consistent pattern, as follows (:pull:`886`, :pull:`1136`):

  • pvlib.pvsystem.snlinverter is now :py:func:`pvlib.inverter.sandia`
  • pvlib.pvsystem.pvwatts_ac is now :py:func:`pvlib.inverter.pvwatts`
  • pvlib.pvsystem.adrinverter is now :py:func:`pvlib.inverter.adr`

• Argument ac_model for :py:class:`pvlib.modelchain.ModelChain` now accepts 'sandia', 'pvwatts' and 'adr' for the inverter models. (:pull:`886`, :pull:`1136`)

• Calling :py:meth:`pvlib.pvsystem.PVSystem.sapm_celltemp` without setting PVSystem.temperature_model_parameters, or a valid combination of PVsystem.module_type and PVsystem.racking_model, will now raise an exception. (:issue:`1030`, :pull:`1033`, :pull:`1136`)

• Deprecated arbitrary keyword arguments for :py:class:`pvlib.location.Location`, :py:class:`pvlib.pvsystem.PVSystem`, :py:class:`pvlib.tracking.SingleAxisTracker`, and :py:class:`pvlib.modelchain.ModelChain`. Supplying arbitrary keyword to these objects result in TypeErrors in v0.9. (:issue:`1029`, :pull:`1053`, :pull:`1136`)

• pvlib.pvsystem.LocalizedPVSystem and pvlib.pvsystem.LocalizedSingleAxisTracker have been removed. Use :py:class:`pvlib.location.Location`, :py:class:`pvlib.pvsystem.PVSystem`, :py:class:`pvlib.tracking.SingleAxisTracker`, and :py:class:`pvlib.modelchain.ModelChain` instead. (:issue:`1029`, :pull:`1034`, :pull:`1053`, :pull:`1136`)

• irradiance.liujordan and ForecastModel.cloud_cover_to_irradiance_liujordan have been removed. (:pull:`1136`)

• ModelChain.snlinverter changed to ModelChain.sandia_inverter. ModelChain.adrinverter changed to ModelChain.adr_inverter. (:pull:`1150`)

• The orientation_strategy parameter has been removed from the various :py:class:`pvlib.modelchain.ModelChain` constructors and surface_tilt, surface_azimuth are now required parameters for pvlib.modelchain.basic_chain (:issue:`1028`, :pull:`1181`)

• Removed the **kwargs parameters from :py:meth:`~pvlib.pvsystem.PVSystem.sapm` and :py:meth:`~pvlib.pvsystem.PVSystem.calcparams_desoto` and :py:meth:`~pvlib.pvsystem.PVSystem.calcparams_cec` (:issue:`1118`, :pull:`1222`)

• Switched the order of the outputs from the PSM3 iotools, notably :py:func:`!pvlib.iotools.get_psm3` and :py:func:`!pvlib.iotools.read_psm3` (:issue:`1245`, :pull:`1268`)

• Changed the naming of the inputs startdate/enddate to start/end in :py:func:`~pvlib.iotools.get_ecmwf_macc` (:issue:`1245`, :pull:`1268`)

• Change the naming of the inputs lat/lon to latitude/longitude in :py:func:`~pvlib.iotools.get_pvgis_tmy` (:issue:`1245`, :pull:`1268`)

Deprecations

• The following ModelChain attributes are deprecated. They have been moved to the :py:class:`~pvlib.modelchain.ModelChainResult` class that is accessible via ModelChain.results:
  • ModelChain.ac
  • ModelChain.airmass
  • ModelChain.aoi
  • ModelChain.aoi_modifier
  • ModelChain.cell_temperature
  • ModelChain.dc
  • ModelChain.diode_params
  • ModelChain.effective_irradiance
  • ModelChain.losses
  • ModelChain.solar_position
  • ModelChain.spectral_modifier
  • ModelChain.total_irrad
  • ModelChain.tracking
  • ModelChain.weather
  • ModelChain.times
• The following PVSystem cell temperature methods have been deprecated and consolidated into the new wrapper method :py:meth:`~pvlib.pvsystem.PVSystem.get_cell_temperature` (:pull:`1211`):
  • :py:meth:`~pvlib.pvsystem.PVSystem.sapm_celltemp`
  • :py:meth:`~pvlib.pvsystem.PVSystem.pvsyst_celltemp`
  • :py:meth:`~pvlib.pvsystem.PVSystem.faiman_celltemp`
  • :py:meth:`~pvlib.pvsystem.PVSystem.fuentes_celltemp`
  • :py:meth:`~pvlib.pvsystem.PVSystem.noct_sam_celltemp`
• The eta_m parameter for :py:func:`~pvlib.temperature.pvsyst_cell` is replaced by parameter module_efficiency. (:issue:`1188`, :pull:`1218`)
• The following attributes of :py:class:`pvlib.pvsystem.PVSystem` and :py:class:`pvlib.tracking.SingleAxisTracker` have been deprecated in favor of the corresponding :py:class:`pvlib.pvsystem.Array` attributes:
  • PVSystem.albedo
  • PVSystem.module
  • PVSystem.module_parameters
  • PVSystem.module_type
  • PVSystem.modules_per_string
  • PVSystem.racking_model
  • PVSystem.strings_per_inverter
  • PVSystem.surface_tilt
  • PVSystem.surface_azimuth
  • PVSystem.temperature_model_parameters
• The :py:class:`pvlib.tracking.SingleAxisTracker` class is deprecated and replaced by using :py:class:`pvlib.pvsystem.PVSystem` with the new :py:class:`pvlib.pvsystem.SingleAxisTrackerMount` (:pull:`1176`)

Enhancements

• Added :func:`~pvlib.iotools.read_pvgis_hourly` and :func:`~pvlib.iotools.get_pvgis_hourly` for reading and retrieving hourly solar radiation data and PV power output from PVGIS. (:pull:`1186`, :issue:`849`)
• Added map_variables option to :func:`~pvlib.iotools.get_pvgis_tmy` and :func:`~pvlib.iotools.read_pvgis_tmy` (:issue:`1250`, :pull:`1268`)
• Add :func:`~pvlib.iotools.get_bsrn` and :func:`~pvlib.iotools.read_bsrn` for retrieving and reading BSRN solar radiation data files. (:pull:`1254`, :pull:`1145`, :issue:`1015`)
• Add :func:`~pvlib.iotools.get_cams`, :func:`~pvlib.iotools.parse_cams`, and :func:`~pvlib.iotools.read_cams` for retrieving, parsing, and reading CAMS Radiation and McClear time-series files. (:pull:`1175`)
• In :py:class:`~pvlib.modelchain.ModelChain`, attributes which contain output of models are now collected into ModelChain.results. (:pull:`1076`, :issue:`1067`)
• Added :py:class:`~pvlib.pvsystem.Array` class to represent an array of modules separately from a :py:class:`~pvlib.pvsystem.PVSystem`. (:pull:`1076`, :issue:`1067`)
• Added :py:class:`~pvlib.pvsystem.FixedMount` and :py:class:`~pvlib.pvsystem.SingleAxisTrackerMount` classes to use with the new :py:class:`~pvlib.pvsystem.Array` class (:pull:`1176`)
• Added capability for modeling a PV system with multiple arrays in :py:class:`~pvlib.pvsystem.PVSystem`. Updates the PVSystem API to operate on and return tuples where each element of the tuple corresponds to the input or output for a specific Array. (:pull:`1076`, :issue:`1067`)
• Support for systems with multiple Arrays added to :py:class:`~pvlib.modelchain.ModelChain`. This includes substantial API enhancements for accepting different weather input for each Array in the system. (:pull:`1076`, :issue:`1067`)
• Support for :py:func:`~pvlib.inverter.sandia_multi` and :py:func:`~pvlib.inverter.pvwatts_multi` added to :py:class:`~pvlib.pvsystem.PVSystem` and :py:class:`~pvlib.modelchain.ModelChain` (as ac_model='sandia' and ac_model='pvwatts'). (:pull:`1076`, :issue:`1067`, :pull:`1132`, :issue:`1117`, :pull:`1150`)
• :py:class:`~pvlib.modelchain.ModelChain` 'run_model' methods now automatically switch to using 'effective_irradiance' (if available) for cell temperature models, when 'poa_global' is not provided in input weather or calculated from input weather data.
• :py:meth:`~pvlib.modelchain.ModelChain.pvwatts_dc` now scales the DC power by pvsystem.PVSystem.modules_per_strings and pvsystem.PVSystem.strings_per_inverter. Note that both attributes still default to 1. (:pull:`1138`)
• :py:meth:`~pvlib.pvsystem.PVSystem.get_ac` is added to calculate AC power from DC power. Use parameter model to specify which inverter model to use. (:pull:`1147`, :issue:`998`, :pull:`1150`)
• Added :py:func:`~pvlib.temperature.noct_sam`, a cell temperature model implemented in SAM. (:pull:`1177`, :pull:`1195`)
• Added :py:func:`~pvlib.ivtools.sdm.pvsyst_temperature_coeff` to calculate the temperature coefficient of power for the pvsyst module model. (:pull:`1190`)
• :py:func:`~pvlib.irradiance.get_total_irradiance` and :py:func:`~pvlib.irradiance.get_sky_diffuse` now fill in airmass if required and not provided. These functions now raise a ValueError if dni_extra is required and not provided. (:issue:`949`, :pull:`1225`)

Bug fixes

• Corrected an error in :py:func:`~pvlib.irradiance.perez` where the horizon irradiance component was prevented from taking negative values. Negative values are intentional according to the original publication. Changes in output are expected to be small and primarily occur at low irradiance conditions. (:issue:`1238`, :pull:`1239`)
• Pass weather data to solar position calculations in :py:meth:`~pvlib.modelchain.ModelChain.prepare_inputs_from_poa`. (:issue:`1065`, :pull:`1140`)
• Reindl model fixed to generate sky_diffuse=0 when GHI=0. (:issue:`1153`, :pull:`1154`)
• Fix floating point round-off issue in :py:func:`~pvlib.irradiance.aoi_projection` (:issue:`1185`, :pull:`1191`)
• Update GFS product names for GFS v16. (:issue:`1202`, :pull:`1203`)
• Take into account EgRef, dEgdT, irrad_ref and temp_ref when calling :py:func:`~pvlib.pvsystem.calcparams_cec`. (:issue:`1215`, :pull:`1216`)
• Corrected methodology error in :py:func:`~pvlib.scaling.wvm`. Tracks with fix in PVLib for MATLAB. (:issue:`1206`, :pull:`1213`)
• Corrected an error affecting :py:func:`~pvlib.clearsky.detect_clearsky` when data time step is not one minute. Error was introduced in v0.8.1. (:issue:`1241`, :pull:`1242`)
• Corrected error affecting :py:func:`~pvlib.scaling._compute_wavelet` when passing a pandas time series with a sampling rate faster than 1 second. (:issue:`1257`, :pull:`1258`)
• Changed deprecated use of .astype() to .view() in :py:mod:`~pvlib.solarposition`. (:pull:`1256`, :issue:`1261`, :pull:`1262`)
• Fix :py:func:`~pvlib.tracking.singleaxis` AOI wrong when sun behind module. (:pull:`1273`, :issue:`1221`)
• Fix :py:meth:`~pvlib.forecast.ForecastModel.get_data` failure to correct for non-UTC timezones. (:issue:`1237`, :pull:`1285`)
• Fixed :py:class:`~pvlib.forecast.HRRR` by changing model name to reflect change on the server. (:issue:`1291`, :pull:`1292`)

Testing

• Added __init__.py to pvlib/tests and subdirectories. This follows pytest recommendations for package layout and imports from conftest.py. Solves issue with test discovery in vscode. (:pull:`1204`)

Documentation

• Update intro tutorial to highlight the use of historical meteorological data and to make the procedural and OO results match exactly. (:issue:`1116`, :pull:`1144`)
• Add a gallery example showing how to appropriately use interval-averaged weather data for modeling. (:pull:`1152`)
• Update documentation links in :py:func:`!pvlib.iotools.get_psm3` (:pull:`1169`)
• Use Mount classes in introtutorial and pvsystem docs pages (:pull:`1267`)
• Clarified how statistics are calculated for :py:func:`pvlib.clearsky.detect_clearsky` (:issue:`1070`, :pull:`1243`)
• Add gallery examples using the new Mount classes (:pull:`1266`)
• Add "powered by pvlib" logos (:pull:`1277`)

Requirements

• dataclasses is required for python 3.6 (:pull:`1076`)
• h5py is now a required dependency. This replaces tables, which was formerly an optional dependency. (:pull:`1299`, :issue:`1252`, :issue:`1286`)

Contributors

• Will Holmgren (:ghuser:`wholmgren`)
• Cliff Hansen (:ghuser:`cwhanse`)
• Will Vining (:ghuser:`wfvining`)
• Anton Driesse (:ghuser:`adriesse`)
• Mark Mikofski (:ghuser:`mikofski`)
• Nate Croft (:ghuser:`nate-croft`)`
• Kevin Anderson (:ghuser:`kevinsa5`)
• Adam R. Jensen (:ghuser:`AdamRJensen`)
• Joshua Stein (:ghuser:`jsstein`)
• Tony Lorenzo (:ghuser:`alorenzo175`)
• Damjan Postolovski (:ghuser:`dpostolovski`)
• Miguel Sánchez de León Peque (:ghuser:`Peque`)
• Joe Ranalli (:ghuser:`jranalli`)
• Chas Schweizer (:ghuser:`cpr-chas`)
• Yoann Louvet (:ghuser:`YoannUniKS`)
• Brandon Carpenter (:ghuser:`hashstat`)
• :ghuser:`kahemker`
• :ghuser:`zhammond147`
• :ghuser:`PeterGrant`
• :ghuser:`rockstaedt`
• :ghuser:`MichaelHopwood`
• :ghuser:`EricDuminil`
• :ghuser:`FeiYao-Edinburgh`