The SATRISE project

Satellite retrieval of 3D Spectral Irradiance to improve the estimation of solar energy production

SATRISE is an ESA-funded innovation project that brings together advanced satellite data and state-of-the-art 3D simulation to redefine how solar irradiance is estimated for photovoltaic (PV) systems. By combining Rayference’s CISAR algorithm with LuciSun’s GPU-based 3D modelling tool, LuSim, SATRISE aims to deliver unprecedented accuracy in solar resource assessment for complex PV applications such as bifacial PV, agrivoltaics, urban PV, and building-integrated photovoltaics (BIPV).

Modern PV installations increasingly use high-resolution 3D models of their surroundings. Yet, today’s irradiance inputs are still based on simplified global horizontal irradiance (GHI), which does not capture how light arrives from different angles or with varying spectral composition. This gap leads to systematic uncertainties—especially in environments where reflections, shading, vegetation, or bifacial effects play a major role.

SATRISE fills this gap by retrieving full 3D angular and spectral irradiance fields from European satellite missions and integrating them directly into next-generation simulation workflows.

Practical cases simulated with LuSim where 3D angular distribution of irradiance is crucial. From left to right: agrivoltaic greenhouse, agrivoltaic orchard, bifacial PV, urban PV.

The new generation of ESA satellite sensors provides rich information about atmosphere, clouds, aerosols, and surface reflectance. With Rayference’s physical-model-based CISAR algorithm, these data can be transformed into detailed downward radiance fields—a unique resource for solar engineering.

SATRISE leverages this capability to:

  • Retrieve spectral and angular irradiance over two test sites in Spain and Denmark.
  • Convert these data into broadband fields usable by PV simulation tools.
  • Integrate them into LuSim for high-resolution 3D irradiance modelling.
  • Validate the improvements using real ground measurements.
  • Assess the economic benefits of more accurate irradiance and yield predictions.

(Insert figure: workflow diagram or satellite–to–simulation pipeline)

Over its 18-month duration, SATRISE will produce:

  1. A validated 3D irradiance dataset

One full year of satellite-derived 3D irradiance fields over both test sites, publicly released for research and industry use.

  1. An enhanced version of LuSim

A prototype capable of ingesting satellite-based angular and spectral irradiance, producing more realistic predictions for:

  • bifacial PV plants,
  • urban and BIPV systems with complex shading,
  • agrivoltaic environments where light distribution affects both crops and PV modules.
  1. Quantified performance improvements

SATRISE will compare traditional GHI-based models with the enhanced satellite-driven approach, demonstrating:

  • reduced uncertainty in plane-of-array irradiance,
  • improved prediction of rear-side irradiance for bifacial PV,
  • more reliable modelling in shaded or heterogeneous environments.
  1. Economic and investment benefits

Because irradiance modelling is at the core of energy yield assessments, improved inputs translate into:

  • better financial indicators (NPV, IRR, WACC),
  • reduced uncertainty for investors,
  • more bankable agrivoltaic and bifacial PV projects.

By combining Earth Observation science with cutting-edge 3D simulation, SATRISE creates the foundation for the next generation of PV design tools. The project directly supports Europe’s energy transition by enabling:

  • more efficient PV systems,
  • better land-use strategies (particularly for agrivoltaics),
  • improved integration of solar energy in urban landscapes,
  • a scalable pathway for commercial services using satellite-based irradiance data.

SATRISE is a collaboration between Rayference and LuciSun, supported by academic test sites in Denmark (DTU) and Spain (University of Jaén), with guidance from leading PV industry partners across Europe.