Forum: Lighter-coloured solar panels could ease heat effect, Forum News & Top Stories
I am referring to the letter from Peter Heng Teck Wee (floating solar parks can do more harm than good to the environment, April 28).
The disadvantages he highlighted mainly relate to the traditional black or dark blue solar panels.
Black solar panels produce more electricity, but can also give off more heat.
Cooling Singapore, a research project to address the urban heat issue, recommends painting roofs, building surfaces, and even streets and footpaths white or light colors to reduce heat build-up.
Therefore, it seems to contradict this recommendation to place dark solar panels on any surface, whether building, land or even water surface.
Solar panels are made from solar cells, which is not the problem. The problem is the black color, which is the best light absorber and allows cells to produce most of the solar energy.
Unfortunately, black is also the best heat absorber.
Up to 85 percent of the absorbed heat is eventually released into the environment, causing the urban heat island effect.
So if black is the problem, would a bright solar panel, such as a light gray one, solve the problem?
Bright solar panels would at least reduce the amount of heat transferred to the environment.
However, while working on solar panels, I realized that any color of solar glass over the black solar cell would significantly reduce the energy efficiency of the solar panels.
Today there are breakthrough technologies that can produce almost the same amount of solar energy as black solar panels.
It is a special glass coating technology that transmits the selected colored wavelength and at the same time allows more than 90 percent of the visible light through the glass to stimulate the black solar cell.
I believe that these colored solar panels with colors that are much lighter than the traditional black or dark blue solar cell should of course be able to mitigate the heat island effect without significantly affecting energy efficiency.