Developer Guide

Integrate the Sunsei API

High-resolution solar power production forecasts powered by the ICON-EU numerical weather prediction model.

Sunsei Model

High-resolution solar power production forecasts for the Europe, driven by the ICON-EU numerical weather prediction model.

  • Forecasts: Updated 4 times per day, with runs starting at 00, 06, 12, and 18 UTC, projecting 120 hours (5 days) ahead. Expect a delay of around 4 hours before a new run becomes available.
  • Archive Forecasts: Historical evaluations of our 5-day forecasts are available from September 2025. From 12 Sep 2025 to 19 Aug 2026 they are available once per day at midnight; from 20 Aug 2026 onward they are available 4 times per day.
  • AC Power: The model was trained on AC power production data.
  • Complete EU Coverage: 23.625°W to 62.375°E in longitude, 29.625°N to 70.375°N in latitude, with a spatial resolution of 0.0625°.

Endpoint Reference

The API is served at https://api.sunsei.ai and exposes three endpoints:

  • /v1/forecast/latest — returns the most recent forecast run for one or more locations.
  • /v1/forecast/historical — returns every forecast run whose forecast time falls inside a date range.
  • /v1/forecast/latest-forecast-time — returns just the timestamp of the newest run, for polling.

Forecast

POST/v1/forecast/latest
Retrieve the latest forecast
POST/v1/forecast/historical
Retrieve historical forecasts
GET/v1/forecast/latest-forecast-time
Get the latest forecast run timestamp

Examples

cURL

Python

Forecast Calibration

Ready to send your first request?

Get your personal API key and connect to our forecasts within minutes.

Get API AccessSee pricing