Performance and efficiency

These terms are often used in order to characterize solar energy conversion systems.

The total efficiency is the product of the individual efficiencies of the different energy conversion processes. It is defined as the fraction of thermal energy entering the cooking pot related to the total sun energy captured by the cooker aperture.

For the Lightoven the individual efficiencies are :

  • Solar reflection of foil: 87%
  • Accuracy of focusing: ~ 80%
  • Transmission heat retention tube: 90%
  • Absorption cooking pot: 95%
  • Thermal efficiency during heating up: ~ 80%
  • Total efficiency: ~ 50%

The total efficiency is similar to a domestic solar water heating system.