Solcast's Historical Time Series and TMY data is available in multiple formats including PVSyst, SAM, TMY3 and the Solcast standard CSV format.

Solcast standard CSV format

The Solcast standard CSV format includes the following parameters and units of measurement:



Period End

Date time of the end of the period.Note that the year is always 2059(or greater) to signify this is sample data, rather than actual data

Period Start

Date time of the start of the period


Length of the averaging period in ISO8601 duration format

Air Temp

The air temperature 2 meters above ground


Solar azimuth angle (degrees). Zero means true north. Varies from -180 to 180. A value of 90 means the sun is in the east

Cloud Opacity

The attenuation of incoming sunlight due to cloud. Varies from 0 (no cloud) to 100 (full attenuation of incoming sunlight)


The dewpoint temperature 2 meters above ground level


The horizontal component of diffuse irradiance


Direct Normal Irradiance. Solar irradiance arriving in a direct line from the sun as measured on a surface held perpendicular to the sun


The horizontal component of direct normal irradiance


The total irradiance received on a horizontal surface. It is the sum of the horizontal components of direct and diffuse irradiance

Precipitable Water

Precipitable water of the entire atmospheric column

Relative Humidity

The air relative humidity 2 meters above ground level

Snow Depth

The snow depth liquid-water-equivalent

Surface Pressure

The air pressure at ground level

Wind Direction

Wind direction (degrees) at 10m above ground level. Zero means true north. Varies from 0 to 360. A value of 270 means the wind is coming from the west

Wind Speed

Wind speed (in m/s) at 10m above ground level.


The angle between a line perpendicular to the earth's surface and the sun (90 deg = sunrise and sunset; 0 deg = sun directly overhead)

Albedo Daily

The average daytime surface reflectivity of visible light, expressed as a value between 0 and 1. 0 represents complete absorption. 1 represents complete reflection


The total irradiance received on a surface with defined tilt and azimuth, fixed or tracking

We provide sample files on our website

You can also use our API Toolkit, along with a Free Tier plan to download data from locations of interest, free of charge.

Lastly, you can even use unmetered locations to access real-world test data via our synchronous TMY P50 API. Check that out in this article.

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