pvlib.iotools.read_tmy3¶
-
pvlib.iotools.
read_tmy3
(filename=None, coerce_year=None, recolumn=True)[source]¶ Read a TMY3 file in to a pandas dataframe.
Note that values contained in the metadata dictionary are unchanged from the TMY3 file (i.e. units are retained). In the case of any discrepencies between this documentation and the TMY3 User’s Manual [1], the TMY3 User’s Manual takes precedence.
The TMY3 files were updated in Jan. 2015. This function requires the use of the updated files.
- Parameters
filename (None or string, default None) – If None, attempts to use a Tkinter file browser. A string can be a relative file path, absolute file path, or url.
coerce_year (None or int, default None) – If supplied, the year of the data will be set to this value.
recolumn (bool, default True) – If True, apply standard names to TMY3 columns. Typically this results in stripping the units from the column name.
- Returns
Tuple of the form (data, metadata).
data (DataFrame) – A pandas dataframe with the columns described in the table below. For more detailed descriptions of each component, please consult the TMY3 User’s Manual ([1]), especially tables 1-1 through 1-6.
metadata (dict) – The site metadata available in the file.
Notes
The returned structures have the following fields.
key
format
description
altitude
Float
site elevation
latitude
Float
site latitudeitude
longitude
Float
site longitudeitude
Name
String
site name
State
String
state
TZ
Float
UTC offset
USAF
Int
USAF identifier
TMYData field
description
TMYData.Index
A pandas datetime index. NOTE, the index is currently timezone unaware, and times are set to local standard time (daylight savings is not included)
TMYData.ETR
Extraterrestrial horizontal radiation recv’d during 60 minutes prior to timestamp, Wh/m^2
TMYData.ETRN
Extraterrestrial normal radiation recv’d during 60 minutes prior to timestamp, Wh/m^2
TMYData.GHI
Direct and diffuse horizontal radiation recv’d during 60 minutes prior to timestamp, Wh/m^2
TMYData.GHISource
See [1], Table 1-4
TMYData.GHIUncertainty
Uncertainty based on random and bias error estimates see [2]
TMYData.DNI
Amount of direct normal radiation (modeled) recv’d during 60 mintues prior to timestamp, Wh/m^2
TMYData.DNISource
See [1], Table 1-4
TMYData.DNIUncertainty
Uncertainty based on random and bias error estimates see [2]
TMYData.DHI
Amount of diffuse horizontal radiation recv’d during 60 minutes prior to timestamp, Wh/m^2
TMYData.DHISource
See [1], Table 1-4
TMYData.DHIUncertainty
Uncertainty based on random and bias error estimates see [2]
TMYData.GHillum
Avg. total horizontal illuminance recv’d during the 60 minutes prior to timestamp, lx
TMYData.GHillumSource
See [1], Table 1-4
TMYData.GHillumUncertainty
Uncertainty based on random and bias error estimates see [2]
TMYData.DNillum
Avg. direct normal illuminance recv’d during the 60 minutes prior to timestamp, lx
TMYData.DNillumSource
See [1], Table 1-4
TMYData.DNillumUncertainty
Uncertainty based on random and bias error estimates see [2]
TMYData.DHillum
Avg. horizontal diffuse illuminance recv’d during the 60 minutes prior to timestamp, lx
TMYData.DHillumSource
See [1], Table 1-4
TMYData.DHillumUncertainty
Uncertainty based on random and bias error estimates see [2]
TMYData.Zenithlum
Avg. luminance at the sky’s zenith during the 60 minutes prior to timestamp, cd/m^2
TMYData.ZenithlumSource
See [1], Table 1-4
TMYData.ZenithlumUncertainty
Uncertainty based on random and bias error estimates see [1] section 2.10
TMYData.TotCld
Amount of sky dome covered by clouds or obscuring phenonema at time stamp, tenths of sky
TMYData.TotCldSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.TotCldUnertainty
See [1], Table 1-6
TMYData.OpqCld
Amount of sky dome covered by clouds or obscuring phenonema that prevent observing the sky at time stamp, tenths of sky
TMYData.OpqCldSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.OpqCldUncertainty
See [1], Table 1-6
TMYData.DryBulb
Dry bulb temperature at the time indicated, deg C
TMYData.DryBulbSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.DryBulbUncertainty
See [1], Table 1-6
TMYData.DewPoint
Dew-point temperature at the time indicated, deg C
TMYData.DewPointSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.DewPointUncertainty
See [1], Table 1-6
TMYData.RHum
Relatitudeive humidity at the time indicated, percent
TMYData.RHumSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.RHumUncertainty
See [1], Table 1-6
TMYData.Pressure
Station pressure at the time indicated, 1 mbar
TMYData.PressureSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.PressureUncertainty
See [1], Table 1-6
TMYData.Wdir
Wind direction at time indicated, degrees from north (360 = north; 0 = undefined,calm)
TMYData.WdirSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.WdirUncertainty
See [1], Table 1-6
TMYData.Wspd
Wind speed at the time indicated, meter/second
TMYData.WspdSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.WspdUncertainty
See [1], Table 1-6
TMYData.Hvis
Distance to discernable remote objects at time indicated (7777=unlimited), meter
TMYData.HvisSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.HvisUncertainty
See [1], Table 1-6
TMYData.CeilHgt
Height of cloud base above local terrain (7777=unlimited), meter
TMYData.CeilHgtSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.CeilHgtUncertainty
See [1], Table 1-6
TMYData.Pwat
Total precipitable water contained in a column of unit cross section from earth to top of atmosphere, cm
TMYData.PwatSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.PwatUncertainty
See [1], Table 1-6
TMYData.AOD
The broadband aerosol optical depth per unit of air mass due to extinction by aerosol component of atmosphere, unitless
TMYData.AODSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.AODUncertainty
See [1], Table 1-6
TMYData.Alb
The ratio of reflected solar irradiance to global horizontal irradiance, unitless
TMYData.AlbSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.AlbUncertainty
See [1], Table 1-6
TMYData.Lprecipdepth
The amount of liquid precipitation observed at indicated time for the period indicated in the liquid precipitation quantity field, millimeter
TMYData.Lprecipquantity
The period of accumulatitudeion for the liquid precipitation depth field, hour
TMYData.LprecipSource
See [1], Table 1-5, 8760x1 cell array of strings
TMYData.LprecipUncertainty
See [1], Table 1-6
TMYData.PresWth
Present weather code, see [2].
TMYData.PresWthSource
Present weather code source, see [2].
TMYData.PresWthUncertainty
Present weather code uncertainty, see [2].
References
[1] Wilcox, S and Marion, W. “Users Manual for TMY3 Data Sets”. NREL/TP-581-43156, Revised May 2008.
[2] Wilcox, S. (2007). National Solar Radiation Database 1991 2005 Update: Users Manual. 472 pp.; NREL Report No. TP-581-41364.