Thermotropic overheating protection for façade-integrated solar thermal collectors

- Application demonstration of thermotropic overheating protection glazing in solar thermal collectors.
- Development of thermotropic formulations exhibiting high long-term stability and weather-ability.
- Six months of in-situ testing in solar thermal collector integrated in south façade of an office building.
- Prove of application relevant overheating protection efficiency.
- Corroboration of theoretical modeling.

The capability of thermotropic glazing to reduce stagnation temperatures in solar thermal collectors is evaluated in in-situ testing (south-façade of an office building). Therefore, a thermotropic formulation which is curable by sunlight and which exhibits both, excellent light-shielding characteristics (transmittance reduction by ~20%) and long-term stability is specifically designed. Application relevant overheating protection efficiency is given: absorber temperatures are reduced by up to 29 K in collector stagnation. Performance characteristics are not changed during the six month period of in-situ testing. The application demonstration emphasizes the high innovative capacity of thermotropic materials.