SunSat is a solar irradiance estimation tool using satellite data. It is a real-time monitoring service available for any site or portfolio of solar installations on the planet.


Hardware-free solution

Hardware-free solution

No matter the number of solar plants in your portfolio, SunSat enables you to get a precise estimation without installing any hardware.

World coverage thanks to 5 geostationary satellites

World coverage thanks to 5 geostationary satellites

Reuniwatt receives the live images of five geostationary satellites, enabling an irradiance estimation service anywhere in the world.

Accurate and reliable data

Accurate and reliable data

SunSat provides accurate and reliable data for already monitored or unmonitored PV plants. Beyond 25 km, ground measurements are less precise than satellite data.




SunSat enables to monitor solar irradiance by using geostationary meteorological satellites. Images provided by the visible channel of the satellite sensor can be converted into global horizontal irradiance (GHI) maps with a proven accuracy.

The use of satellite data for real-time estimation in a purpose of monitoring offers many advantages compared to sole in-situ measurements:

  • Unbiased and independent vision of the estimated irradiance over a plant or a portfolio of installations
  • Quick detection of any instrumental failure or soiling by comparing actual power generation and satellite estimation
  • Immediate and affordable set-up (no hardware needed)
  • Larger field of view (macroscopic vision vs microscopic vision)

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Global coverage

Easy visualisation and data download via our Myriad platform

Time resolution down to 10 minutes (30 minutes max depending on the satellite)

For a single site or a portfolio of PV installations

Possible access to real time data or historical time series reconstruction