New cermet coatings for mid-temperature applications for solar concentrated combine heat and power system
2014 (English)In: Proceedings of the 2ND International Conference on Solar Heating and Cooling for Buildings and Industry (SHC 2013) / [ed] Haberle, A, 2014, 242-249 p.Conference paper (Refereed)
New cermet (ceramic-metal) composite coatings have been developed for solar absorbers in a solar concentrating system for combined heat and power operating in a mid-temperature range between 250 to 350 degrees C. The coatings were applied on stainless steel substrates. Two types of cermet with expected good duration properties were chosen: Nb-TiO2 and W-SiO2. The basic layer-structure concept consisted of four sub-layers, counted from the substrate: molybdenum infrared reflector, high metal concentration cermet of either Nb-TiO2 or W-SiO2, low metal concentration cermet of either Nb-TiO2 or W-SiO2 and SiO2 antireflection layer. The results from optimised coating fabrication gave solar absorptance and thermal emittance of 0.93 and 0.09 respectively for the Nb-TiO2 cermet and 0.91 and 0.08 for the W-SiO2 cermet based absorbers. Annealing at 350 degrees C did not change the absorptance but decreased the thermal emittance with 0.01 units. Adhesion to substrate and between sub-layers was good and even improved after annealing. In a next step up-scaling to deposition on tubes has been made for the Nb-TiO2 cermet type coating and such absorbers are now operating in the solar concentrating combined heat and power demonstration plant in Malta.
Place, publisher, year, edition, pages
2014. 242-249 p.
, Energy Procedia, ISSN 1876-6102 ; 48
solar absorber, cermet coating, sputtering-deposition
Environmental Analysis and Construction Information Technology
IdentifiersURN: urn:nbn:se:uu:diva-240883DOI: 10.1016/j.egypro.2014.02.029ISI: 000345410700028OAI: oai:DiVA.org:uu-240883DiVA: diva2:777580
2nd International Conference on Solar Heating and Cooling for Buildings and Industry (SHC), SEP 23-25, 2013, Freiburg, GERMANY