Warning! It is strongly recommanded to avoid the launch of parallel requests, using the "&" at the end of each wget request line. This would endanger our system.
 

Automatic access with WGET

In brief, as soon as a new Meteosat image is available every 15 min, the HelioClim-3 database is updated in real time. To receive a time series covering the whole current day, we decided to complete the time series by applying a persistence model.

1. Subscribe an annual access to HelioClim-3 Current Day service (Contact us)
2. Download wget.exe in a directory (on Windows - wget is available by default on Unix)
3. In the same directory, create a text file and copy-paste in a single line the following instruction to test this permanent access to Carpentras, France:

4. Rename the text file with the .bat extension and double click on it to retrieve the output.csv output file in a Windows environment. Rename the text file with a .sh extension and run it using ./my_script.sh in a Unix environment.

  WGET, in details

Request:
wget -O output.csv --header="soda-user: login" --header="soda-passwd: password" ...
"https://server/pub/hc3v5_persistence_forecast.php?geopoint=latitude,longitude&elevation=altitude ...
&firstday=yyyy-mm-dd&lastday=yyyy-mm-dd&duration=time_step&time=time_reference&slope=tilt_of_panels ...
&azimuth=az_of_panels&albedo=ground_albedo&horizon=boolean_horizon&format=output_format&calibration=calib_name"

Inputs:

• login/password authentication: login and password provided by the SoDa team to access HelioClim-3 within the framework of your subscription. Note that a free permanent automatic access is set up for the site of Carpentras, France, where a Baseline Surface Radiation Network (BSRN) station is available with the login/password guest/guest
• server: By default, use our load balancer thanks to "api.soda-solardata.com". It will redirect your request on the fastest server available.
  
• latitude and longitude: in degrees, with at least 4 digits after comma
• altitude: in meters. Set "elevation=-999" to let SoDa get the elevation from Nasa SRTM database
• yyyy-mm-dd: set the first and the last days of the request. Use "d" for the current day
• time_step: set the interval among "1", "5", "10", "15", "30", "60"
• time_reference: "UT" (universal time) or "TST" (True Solar Time)

tilt_of_panels: from "0" (horizontal) to "90", or "-999" for tracking. az_of_panels: from "0" (North), "90" (East), "180" (South) to "270" (West), or "-999" for tracking. ground_albedo: from "0.0" to "1.0". A usual inland value is "0.2" More details on plane orientations and on how to set the tilt, azimuth and albedo parameters =>

• boolean_horizon: optional. Takes into account "1" or not "0" the shadowing effect due to the far horizon. If not set, default value is "0"
• output_format: optional. Possible values are standard formats "excel", "netcdf" and "json"; "unified" to get Unified csv format; "classic" for Classic csv format (deprecated). Default format is "classic" for HC3 requests without meteo data. For HC3 requests with meteo data, the "classic" format is not supported and the default format is "unified".
• calib_name: calibration name (default is none). Please refer to the page describing our calibration procedure or/and contact us to ask your questions and receive a quotation.

Outputs: The differences with time series retrieved via the Web interface are:

• the separator is the space for the "classic" HC3 format and the semi-colon for the "unified" HC3 format.
• the time period max retrieved using the wget command is: one month for a 1 to 5 min time step, one year for a 10 min up to one hour time step, and unlimited for the other time steps.

⇒ To add meteorological data along with the solar radiation data in the same file (format "unified" only):

Automatic access using CURL

You can also automatically retrieve time series using the CURL command. The advantage is two fasten the requests by an approx. factor of 2. Note that all parameters described in the WGET section are valid for CURL, except that CURL outputs don't have any header.

Request:
curl -f -s -S -F stations=@stations.txt -o output.csv --header "soda-user: guest" ...
--header "soda-passwd: guest" https://api.soda-solardata.com/pub/hc3v5_persistence_forecast.php

With the following stations.txt file format:
# Columns:
# id: station name
# latitude and longitude: in degrees, with at least 3 digits after comma
# altitude: in meters. Use -999 to let SoDa get the elevation from Nasa SRTM database.
# time reference: "UT" (universal time) or "TST" (True Solar Time)
# duration: "15" (minutes), "h" (hourly), "d" (daily), "m" (monthly)
# firstday and lastday: first and last days of the request. Use "d" for current day.
# slope of panel: from "0" (horizontal) to "90" (deg). Use -999 for sun tracking.
# azimuth of panel: from 0° (North), 90° (East), 180° (South), ... Use -999 for sun tracking.
# ground_albedo: from "0.0" to "1.0". A usual inland value is "0.2".
# horizon: "0" to ignore relief shadows (default), "1" or "SRTM" for an horizon computed from SRTM
# calibration: calibration name (default is none)
# format: output file format. Possible values are "classic" (default) or "unified" for HC3. The only possible value is "unified" for HC3+METEO.
#
#id        lat    lon   elevation time duration firstday   lastday    slope azimuth albedo horizon calibration format
Carpentras 44.083 5.059 -999      UT   15       d d+1 15    180     0.2    1        ""         unified
...

⇒ To add meteorological data along with the solar radiation data in the same file (format "unified" only):