II. İLERİ TEKNOLOJİLER ÇALIŞTAYI (İTÇ 2011) - Bilgesam

FROM FUNDAMENTAL TO APPLIED
ELECTROCHEMISTRY ELECTROCHEMICALLY
NANO-COATED SELECTIVE SURFACES
Prof. Dr. Figen KADIRGAN
Selektif Teknoloji San. Tic. Ltd.
Outline
� Introduction
� Fundamental Outlook of Solar Thermal conversion
� Preparation of Nano layers using electrochemistry
� Testing and accreditation of the selective surfaces
� Life Cycle Analysis of the production
Introduction
� Solar energy seems to be one of the attractive and promising alternative energy
sources for Turkey. Turkey is fortunate because it has about 2640 hours
of sunshine annually and the total annual solar radiation (on a south oriented
area, tilted 45 o ) is about 1460 kW/m 2 in most of the regions.
� Flat plate solar collectors have been extensively used mainly in the southern
and western regions of Turkey for Domestic Hot Water (DHW) since 1975.
The absorber plates of these conventional collectors are painted with matt
black paint, which has a very poor absorption/emission ratio. Furthermore,
the black paint cracks and fades with time losing its characteristic and hence
reducing the lifetime of the collectors.
� The survey on the solar collector market, indicated that there is a tremendous
need for high efficiency solar collectors to supply DHW. The development
of high efficiency solar collectors will provide more energy saving and
wider applicability .
Fundamental Outlook of Solar Thermal conversion
High efficiency collectors must have selective and protective coatings on absorber
plates. An efficient coating is defined as having a high absorbance α over the solar
spectrum (∼0.3-2 μm), but in addition, having a low emittance (ε) to reduce thermal
radiative heat losses.
The type of coating proves significant as a criterion that determines the quality of
the absorber sheet. For this coating to perform efficiently under solar radiation, its
radiation properties should be as required.
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