Colour coming to solar thermal facades

Researchers at the Shanghai Institute of Technical Physics have come up with a new technology that will allow solar thermal collectors on building facades to be in vibrant colours.
Reported in Optics Express, a journal of the Optical Society, the solar light absorbing technology is being developed by a team headed by Shao-Wei Wang.
Solar selective absorbers are used on buildings to heat water and sometimes to generate electricity by generating steam. They consist of layered surfaces that absorb sunlight.
Unfortunately to date most solar absorbing materials were black or blue, since other colours either could not absorb all the solar wavelengths or they emitted a lot of infrared light. Also each absorber had to be the same colour. These limitations meant that designers who wanted to incorporate these energy-saving, sustainable technologies in their buildings had to settle for dull and monotone exteriors.
Shawo-Wei Wang’s new technology covers the solar absorber with multiple layers of transparent dialectric materials. The thickness of the layers can be varied to change the shades, and different mosaics of different vibrant colours can be achieved.
Click here to read further details, read this article in phys.org