pvanalytics.features.clearsky.reno(ghi, ghi_clearsky)#

Identify times when GHI is consistent with clearsky conditions.

Uses the function pvlib.clearsky.detect_clearsky().


Must be given GHI data with regular (constant) time intervals of 15 minutes or less.

  • ghi (Series) – Global horizontal irradiance in \(W/m^2\). Must have an index with time intervals of at most 15 minutes.

  • ghi_clearsky (Series) – Global horizontal irradiance in \(W/m^2\) under clearsky conditions.


True when clear sky conditions are indicated.

Return type



ValueError – if the time intervals are greater than 15 minutes.


Clear-sky conditions are inferred when each of six criteria are met; see pvlib.clearsky.detect_clearsky() for references and details. Threshold values for each criterion were originally developed for ten minute windows containing one-minute data 1. As indicated in 2, the algorithm also works for longer windows and data at different intervals if threshold criteria are roughly scaled to the window length. Here, the threshold values are based on [1] with the scaling indicated in [2].

Copyright (c) 2019 SolarArbiter. See the file LICENSES/SOLARFORECASTARBITER_LICENSE at the top level directory of this distribution and at https://github.com/pvlib/pvanalytics/blob/master/LICENSES/SOLARFORECASTARBITER_LICENSE for more information.



Reno, M.J. and C.W. Hansen, “Identification of periods of clear sky irradiance in time series of GHI measurements” Renewable Energy, v90, p. 520-531, 2016.


B. H. Ellis, M. Deceglie and A. Jain, “Automatic Detection of Clear-Sky Periods From Irradiance Data,” in IEEE Journal of Photovoltaics, vol. 9, no. 4, pp. 998-1005, July 2019. doi: 10.1109/JPHOTOV.2019.2914444

Examples using pvanalytics.features.clearsky.reno#

Clear-Sky Detection

Clear-Sky Detection