Abrasion

Glass Abrasion Tester
© Fraunhofer CSP
The abrasion tester developed at Fraunhofer CSP can be used to test the resistance of surfaces to cleaning processes.

Due to the accumulation of dust and other contaminants on the surfaces of photovoltaic modules or solar thermal mirrors (CSP), significant yield losses can occur. To avoid these, regular cleaning of the glass surfaces is usually carried out.

This regular cleaning results in high mechanical loads on the glass surfaces, which nowadays are usually provided with anti-reflective coatings. Damage to these coatings due to cleaning leads to significant, irreversible losses in yield, which means high financial risks for plant operators, investors and plant manufacturers.

Fraunhofer CSP operates standardized test facilities with which surfaces of solar energy systems (up to PV module formats) can be tested with regard to their resistance to real cleaning loads in Europe and desert regions. In addition, the damage potential of user-specific cleaning parameters and materials can be evaluated at Fraunhofer CSP.

Test Washing System for Rotating Brush Cleaning

Prüfwaschanlage
The large-area test washing system offers the possibility of full-surface abrasion tests with wet-rotating brush cleaning and defined dust-water suspensions.
Bürsten_Prüfwaschanlage
The abrasion resistance of coatings to standardized and application-specific cleaning loads with different brush types can be tested.
  • full-surface abrasion tests with wet-rotating brush cleaning with defined dust-water suspensions.
  • working mode 1 (normative quantitative): testing the abrasion resistance of coatings to standardized cleaning loads (defined test dust, defined brush and cleaning parameters)
  • working mode 2 (normative qualitative):evaluation of the damage potential of user-specific brushes and cleaning parameters against standard cleaning conditions from working mode 1 (e.g. comparison of test dusts, brush types, brush speeds)
  • in-situ determination of the abrasion-induced reduced anti-reflection effect by means of optical reflection spectroscopy
  • recording of the reflectance increase (due to ARC degradation) as a function of the number of brush cycles
  • rotating brush abrasion tests can be performed on defined contaminated samples on request

Mobile Abrasion Tester for Linear Brush Cleaning

Abrasion teste
Abrasion tester developed at Fraunhofer CSP for testing the resistance of surfaces to cleaning processes.
  • small area abrasion tests with linear brush cleaning with defined test dust
  • dry cleaning (wet cleaning on request)
  • homogeneous distribution of initially 1 g dry Arizona test dust A2 fine (defined in ISO 12103) on the glass surface, reapplication of 0.5 g dust every 100 cycles
  • typical set of test cycles: 100, 200, 300, 400 and 500
  • evaluation of transmittance and reflectance after each test cycle according to IEC 62805-2
  • linear brush abrasion tests can also be performed on defined contaminated samples upon request