Once you've made your request for historical data and the request is completed, the data will be available in .csv format which you can access from the Solcast API Toolkit, or you can download from the confirmation email we send to you.
Depending on the parameters you selected when making the request, the .csv file may have different columns listed in the .csv file.
For all historical requests, the following is a list describing the columns that will always appear in your .csv file:
- Period End: The date of the measurement in UTC
- Period: The interval of the measurement in ISO 8601 standard (i.e. PT5M = 5 minutes)
- Latitude: The latitude of the location
- Longitude: The longitude of the location
- Distance: The distance in kilometers between the location defined in the request and the sampled location (the nearest location where Solcast has data available)
Then, depending on the parameters you chose in your historical request, the following is a list describing the columns that may appear in your .csv file:
- Global Horizontial Irradiance (GHI): The total irradiance received on a horizontal surface. It is the sum of the horizontal components of direct (beam) and diffuse irradiance.
- Direct (Beam) Horizontal Irradiance (EBH): The horizontal component of Direct Normal Irradiance.
- Direct Normal Irradiance (DNI): Solar irradiance arriving in a direct line from the sun as measured on a surface held perpendicular to the sun.
- Diffuse Horizontal Irradiance (DHI): The horizontal component of diffuse irradiance (irradiance that is scattered by the atmosphere).
- Air temp: The temperature of the air in the given location (10 meters above ground level).
- Zenith: The angle between a line perpendicular to the earth's surface and the sun (90 deg = sunrise and sunset; 0 deg = sun directly overhead).
- Azimuth: The angle between a line pointing due north to the sun's current position in the sky. Negative to the East. Positive to the West. 0 at due North.
- Cloud Opacity: The measurement of how opaque the clouds are to solar radiation in the given location.