1. Overview
A typical meteorological year (TMY) is a set of meteorological data with data values for every hour in a year for a given geographical location. The data are selected from hourly data for the full time period available, currently 2005-2020 in PVGIS 5.2 and 2005-2016 in PVGIS 5.1.
PVGIS generates a TMY following the ISO 15927-4 procedure. The methodology is further described in the open access publication: T. Huld et al, Assembling Typical Meteorological Year Data Sets for Building Energy Performance Using Reanalysis and Satellite-Based Data, Atmosphere 2018, 9, 53; doi:10.3390/atmos9020053.
The TMY tool can be used to interactively visualise all data or to download in CSV, json or epw file formats.
The solar radiation database (DB) used is the default DB for the given location, either PVGIS-SARAH, PVGIS-NSRDB or PVGIS-ERA5. The other meteorological variables are obtained from ERA-Land reanalysis data in the case of PVGIS 5.2 and ERA-Interim for PVGIS 5.1.
The tool can be accessed with:
- PVGIS interface - TMY tab
- Non-interactive service - tmy app
2. Outputs
2.1 csv
The CSV output contains a header with the following information:
- Latitude [decimal degrees]
- Longitude [decimal degrees]
- Elevation [m]
- A list of years used for each month to construct the TMY. If the full time series is requested, this list will not be included in the output.
After this follows the header line for the actual data. The consist of 1 year (or several years) of hourly data, each hour on a separate line, with the following columns:
- Date & time (UTC)
- T2m [°C] - Dry bulb (air) temperature.
- RH [%] - Relative Humidity.
- G(h) [W/m2] - Global horizontal irradiance.
- Gb(n) [W/m2] - Direct (beam) irradiance.
- Gd(h) [W/m2] - Diffuse horizontal irradiance.
- IR(h) [W/m2] - Infrared radiation downwards.
- WS10m [m/s] - Windspeed.
- WD10m [°] - Wind direction.
- SP [Pa] - Surface (air) pressure.
Please also note that the timestamp is HH:00, but returns values corresponding to the PVGIS-SARAH (HH:MM) or ERA5 (HH:30) timestamps, depending on the database used for solar radiation.
2.2 json
{ "inputs": { "location": {
"latitude": 45.809,
"longitude": 8.632,
"elevation": 223 },
"meteo_data": {
"radiation_db": "PVGIS-SARAH",
"meteo_db": "ERA-Interim",
"year_min": 2005,
"year_max": 2014,
"use_horizon": true,
"horizon_db": "DEM-calcualted",
} },
"outputs": {
"months_selected": {
{
"month": 1,
"year": 2007 },
{...}
},
"tmy_hourly": {
{
"time": "20070101:0000",
"T2m": 5.23,
"RH": 79.72,
"G(h)": 0,
"Gb(n)": 0,
"Gd(h)": 0,
"IR(h)": 242.14,
"WS10m": 1.92,
"WD10m": 30,
"SP": 100570,
},
{...}
}
},
"meta": { "inputs": {
"location": {
"description": "Selected location"
"variables": {
"latitude": {
"description": "Latitude",
"units": "decimal degrees"
},
{...}
}
},
{...}
},
"outputs": {
"months_selected": {
"type": "time series"
"timestamp": "monthly"
"description": "months selected for the TMY"
},
{...}
}
}
}
2.3 epw
This is the format used by the open source EnergyPlus software, the file extension is ".epw". For this format, consult the EnergyPlus documentation
Note that that the date & time timestamp is local time for the EPW format. Also, the format requires that each variable is reported with a value corresponding to the amount during the hour preceding the time indicated. The PVGIS .epw data series therefore starts at 01:00, but reports the same values as for the .csv and .json files at 00:00.