Skip to content

Forecast Data API

Get irradiance, weather and power forecasts from the present time up to 14 days ahead for the requested location, derived from satellite (clouds and irradiance over non-polar continental areas, nowcasted for approx. four hours ahead) and numerical weather models (other data and longer horizons).


The module ForecastClient has the following available methods:

Endpoint Purpose API Docs
GetRadiationAndWeather Get irradiance and weather forecasts for the requested location from the present up to 14 days ahead, derived from satellite (clouds and irradiance over non-polar continental areas, now casted for approx. four hours ahead) and numerical weather models (other data and longer horizons). details
GetRooftopPvPower Get basic rooftop PV power forecasts from the present time up to 14 days ahead for the requested location, derived from satellite (clouds and irradiance over non-polar continental areas, nowcasted for approx. four hours ahead) and numerical weather models (other data and longer horizons). The basic rooftop power simulation is only suitable for residential and smaller C&I rooftop sites, not for grid-scale sites. Attention hobbyist users If you have a hobbyist user account please use the Rooftop Sites (Hobbyist) endpoints. details
GetAdvancedPvPower Get high-spec PV power forecasts for the requested site from the present up to 14 days ahead, derived from satellite (clouds and irradiance over non-polar continental areas, nowcasted for approx. four hours ahead) and numerical weather models (other data and longer horizons). details

GetRadiationAndWeather

Parameters: latitude, longitude, hours, period, tilt, azimuth, arrayType, outputParameters, terrainShading, format

Example Usage:

using Solcast.Clients;

var forecastClient = new ForecastClient();
var response = await forecastClient.GetRadiationAndWeather(
    latitude: -33.856784,
    longitude: 151.215297,
    period: "PT30M",
    tilt: 30.0f,
    azimuth: 180.0f,
    format: "csv"
);
Console.WriteLine(response.RawResponse);
Sample Output:

air_temp dni ghi period_end period
23 795 919 2025-02-18T01:30:00Z PT30M
24 820 948 2025-02-18T02:00:00Z PT30M
... ... ... ... ...
21 17 418 2025-02-20T01:00:00Z PT30M
20 3 412 2025-02-20T01:30:00Z PT30M

GetRooftopPvPower

Parameters: latitude, longitude, capacity, hours, period, tilt, azimuth, installDate, lossFactor, outputParameters, terrainShading, format

Example Usage:

using Solcast.Clients;

var forecastClient = new ForecastClient();
var response = await forecastClient.GetRooftopPvPower(
    latitude: -33.856784,
    longitude: 151.215297,
    capacity: 5.0f,
    format: "csv"
);
Console.WriteLine(response.RawResponse);
Sample Output:

pv_power_rooftop period_end period
3.739 2025-02-18T01:30:00Z PT30M
3.836 2025-02-18T02:00:00Z PT30M
... ... ...
1.678 2025-02-20T01:00:00Z PT30M
1.647 2025-02-20T01:30:00Z PT30M

GetAdvancedPvPower

Parameters: resourceId, hours, outputParameters, period, applyAvailability, applyConstraint, applyDustSoiling, applySnowSoiling, applyTrackerInactive, terrainShading, format

Example Usage:

using Solcast.Clients;

var forecastClient = new ForecastClient();
var response = await forecastClient.GetAdvancedPvPower(
    resourceId: "ba75-e17a-7374-95ed",
    format: "csv"
);
Console.WriteLine(response.RawResponse);
Sample Output:

pv_power_advanced period_end period
10 2025-02-18T01:30:00Z PT30M
10 2025-02-18T02:00:00Z PT30M
... ... ...
8.155 2025-02-25T01:00:00Z PT30M
8.049 2025-02-25T01:30:00Z PT30M