Performance losses due to light load - the so-called light-induced degradation (LID) - affects all types of solar cells and PV modules. Other materials, such as polymers or conductive adhesives, also age under the influence of light. Fraunhofer CSP has developed a test rig that quantifies LID under precisely defined degradation conditions.

Degradation Test LightSoaker
© Fraunhofer CSP
The lightsoaker is prepared for a degradation test.
CTM Tester
© Fraunhofer CSP
CTM Tester
LightSoaker test units
© Fraunhofer CSP
LightSoaker with four test units.


  • Long-term illumination with variable spectrum and up to 2000 W/m² intensity for LID tests on all PV technologies
  • Exactly definable test sequences for accelerated degradation due to increased temperatures up to 130°C via temperature-controlled sample holders
  • Combined tests by simultaneous light and current load
  • Real-time monitoring of degradation parameters


Benefits and Advantages

  • Reliable and standard-compliant quality control of new cell technologies and module materials for photovoltaics
  • Cost reduction in development through accelerated process development
  • Long-term tests under stable, reproducible conditions for comparative tests and market screening


Application Examples

  • Development of new test methods for light and elevated temperature induced degradation (LeTID)
  • Construction of new test rigs as well as measurement and test recipes for specific rapid tests of individual degradation mechanisms