Ageing test procedure for thermal solar collectors

(Nanowerk News) In the project SpeedColl accelerated ageing test procedures for thermal solar collectors and their components are developed. This joint project is being conducted by the Research and Test Centre for Solar Thermal Systems (TZS) at the Institute for Thermodynamics and Heat Technology (ITW) by the University of Stuttgart and the Fraunhofer Institute for Solar Energy Systems (ISE) in Freiburg as well as by industrial project partners. The project consortium has now met for a “summit meeting” on the Zugspitze in order to examine the solar collectors exposed there after a two-year test operation.
Due to the extreme weather conditions and the high level of UV radiation, the Zugspitze was selected as one of the six exposure locations worldwide to test solar collectors and components of solar thermal systems. The project takes up the still low level of knowledge to date regarding the ageing of solar collectors in different climate zones. Through their operation in different surrounding conditions, such as extreme temperatures, UV radiation, salt contamination and dampness, solar collectors are the components in a thermal solar system bearing the greatest load. In order to get statements about the longevity of solar collectors under different climate conditions, these influential factors are to be reproduced through fast-track procedures in the laboratory.
It is important for investors and users that solar collectors can also withstand extreme climatic influences in the long term. The quality of the products is of great significance, in particular also for developing new markets by the German industry. SpeedColl is the first project in solar thermal energy in which many collectors and components are exposed with simultaneous climate and component monitorium in different climate zones.
No significant changes to the serial products could be ascertained by the scientists with the visual test bench inspections on the Zugspitze. The results of the climate and component monitorium also resulted in the absorption temperatures (collector temperatures) showing no significant changes after two years of exposure.
Dr.-Ing. Harald Drück, Head of Department at the Institute for Thermal Dynamics and Heat Technology (ITW), underlined the innovative character of the project and commented on the test operation on the Zugspitze: “The research institutes ITW and ISE as well as the German industry are making a decisive contribution with the project SpeedColl in order to continue to make high quality and favourably priced solar thermal collectors and systems that serve the purpose of climate protection available to the global market in the future as well.“
In view of the dramatic climate scenario depicted by the WMO (World Meteorological Organization), the use of regenerative energies to reduce the CO2 burden in the atmosphere is vital. The particularly effective heat generation through solar thermal systems is thereby given a key position when we consider that around 2/3 of the worldwide energy requirement is heat energy. Over 12 GW solar thermal output resp. approx. 17 million m² collector surface is already installed today in Germany. Each year over 1 million tons of CO2 emissions are now already avoided through this.
Source: Universität Stuttgart