Selective absorbers for Solar Applications
What we offer:
A patented method is used to produce selective absorbers for solar applications with sol-gel dip coating method. High temperature, air stable at 500ºC, selective absorbers are produced with a solar absorptance of 0,96 and a thermal emittance of 0,087 at 400ºC and 0,11 at 500ºC. Thermal stability of selective absorbers deposited on 304 stainless steel has been studied in air, at 500ºC, during six months without any change in optical properties.
High temperature selective absorber can be deposited over any austenitic stainless steel and is composed of six different layers. Infrared reflector, employed to assure high stability at 500ºC in air, is platinum with a minimum thickness (40 nm) to control absorber cost.
This deposition method allows tailoring optical properties of the absorber and it is possible to reduce thermal emittance with a small solar absorptance penalty.
Main application of this absorber is CSP receiver production.
Medium temperature (<350ºC) solar selective absorbers can be produced, on aluminium sheets for flat collectors or tubes for CSP industrial heating systems. Aluminium substrate is used as infrared reflector and the absorber has three layers on top. Solar absorptance is closed to 0,95 with a thermal emittance lower than 0,05 at 300ºC.
In order to evaluate the durability of these absorbers the test procedure developed by the IEA within the “Solar Heating and Cooling Program Task X” for low-temperature absorbers, was applied with excellent results, with a performance criteria (PC) of 0,003.
What we are looking for:
We are interested in licensing the patent.