---
title: "Observed solar radiation (EUMETSAT CM SAF SARAH-3)"
method: GET
path: "/api/v2/energy/solar"
tags: ["Energy"]
---

# Observed solar radiation (EUMETSAT CM SAF SARAH-3)

`GET /api/v2/energy/solar`

Satellite-derived OBSERVED daily surface solar radiation at any coordinate on the Meteosat 0-degree disc (Europe, Africa, the Atlantic, eastern South America): global horizontal (SIS), direct horizontal (SID), direct normal irradiance (DNI - the PV-relevant beam component a forecast surface does not observe) and sunshine duration (SDU), on the native 0.05 degree SARAH-3 grid. An observed climate data record at about a 3-day publication lag - not a forecast (use /api/v2/weather for forecasts). CC BY 4.0 (EUMETSAT Data Policy Core).

## Query parameters

- `lat` number, required — Latitude, decimal degrees.
- `lon` number, required — Longitude, decimal degrees.

## Response `200`

Successful Response

- EnvelopeSolarFeed
  - `data` SolarFeed, required
    - `location` SolarLocation, required
      - `requested` object, required — The requested lat/lon.
      - `tile` string, required
      - `node` SolarNode, required
        - `lat` number, required — Sampled grid-node latitude (0.05 degree SARAH-3 grid).
        - `lon` number, required — Sampled grid-node longitude.
    - `date` string, required — Observed day (SARAH-3 publishes at ~3 days lag).
    - `values` SolarValues, required
      - `sis` number, nullable — Surface incoming shortwave (global horizontal) daily mean, W m-2.
      - `sid` number, nullable — Surface direct (horizontal) daily mean, W m-2.
      - `dni` number, nullable — Direct normal irradiance daily mean, W m-2 - the PV-relevant beam component.
      - `sdu` number, nullable — Sunshine duration daily sum, hours.
    - `units` object — Units per variable, read from the tile records.
    - `coverage_note` string, nullable — Set when the node lies inside the tile set but outside the Meteosat disc (all values null).
    - `provenance` SolarProvenance, required
      - `institution` string, required
      - `model` string, required
      - `grid` string, required
      - `run` string, nullable — The observed day, ISO 8601 UTC midnight.
      - `variables` string[] — Variables published for this date.
    - `attribution` object, required — CC BY 4.0 attribution set (EUMETSAT / CM SAF SARAH-3).
    - `methodology` string, required
    - `disclaimer` string, required
  - `meta` SugraMeta, required — Metadata attached to every /api/v1/* response envelope.
    - `endpoint` string, required — Requested endpoint path.
    - `data_time` string, required — ISO 8601 UTC timestamp of the source data, not of the request.
    - `response_time` string, required — ISO 8601 UTC timestamp when this response was produced.
    - `provider` string, required — API name and version.
    - `source` string, nullable — Identifier of the primary upstream source used for this response.
    - `attribution` string, nullable — Human-readable attribution mandated by an upstream source (e.g. a securities regulator or self-regulatory organization). Present only on responses whose source requires the owner and source to be clearly identified. Do not remove or alter it when using the response.
    - `fallback_used` boolean, nullable — True when the primary source failed and a fallback produced the data.
    - `fallback_chain` string[], nullable — Ordered list of sources attempted, in the order they were tried.
    - `cached` boolean, nullable — True when this response was served from the internal cache.
    - `stale` boolean, nullable — True when the cached response was returned after the upstream rate-limited or errored. Clients can use this to detect degraded data.

## Other responses

- `401` — Missing or invalid `x-api-key` header.
- `422` — Validation Error
- `429` — Daily rate limit exceeded. Check `X-RateLimit-Reset` for the next window.
- `503` — Upstream source is temporarily unavailable. Retry after a short delay.

---

[API](https://skmtc.net/sugra/apis/sugra-api.md) · [All operations](https://skmtc.net/sugra/apis/sugra-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/sugra/sugra-api/versions/dcf7427e6897/schema)