A number of things affect the overall efficiency of the solar collector. For example, efficiency depends on the time of day, the season of the year, the latitude of the area, weather conditions, and the color of the collector.
To many people's surprise, the color of the solar collector can have a drastic impact on how effective it is. There is a direct relationship between the amount of heat that is absorbed by a solar collector and the color of the collector.
While solar collectors come in a wide array of colors, dark colors tend to absorb more heat than light colors. In addition, you will find that shiny colors simply reflect away from the collector. Over the past decade or so, the study of colors and absorption of energy has become an extremely important issue all because energy efficiency is affected by this absorption.
There is no question that black is going to absorb solar heat the best out of any color. As an everyday example, think about how you try to avoid wearing black on how summer days because it absorbs so much heat! The same can be said about heating your home: black solar collectors will attract and absorb the most solar heat.
Solar radiation is made up of electromagnetic energy of various wavelengths. As it passes through the earth's atmosphere, half is reflected back into space while the other half makes its way to the surface of the earth. The air molecules react with this incoming radiation, scattering the light and absorbing most of the harmful rays. The filtered energy is what see and feel as sunshine.

Solar cells are made out of N-type and P-type semiconductor material that use the visual light spectrum to generate electricity. Solar radiation with wavelengths of 380 nm to 750 nm (violet to red) strike the material with enough energy to knock electrons from their weak bonds and create an electric current. The unused wavelengths (ultraviolet & infrared) do not have enough energy to dislodge the electrons and are absorbed as heat.
Full-Spectrum Photovoltaic MaterialWith existing solar cells, the unused ultraviolet and infrared wavelengths are not converted into electricity but rather wasted as heat. A recent discovery of a new semiconductor material made from indium, gallium and nitrogen can convert virtually the full spectrum of sunlight - from the far ultraviolet to the near infrared - into electricity. One panel can use the entire electromagnetic spectrum and holds promise of being the most efficient solar panel ever created.
(For those interested there are specific solutions being created called ORMES that contain these rare elements.Contact through email if interested.-DH)
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You are the solar collector when you begin this particular Qi Gong. Please dress accordingly for these early morning exercises and use the necessary sun protection suited to your skin color. Do not peer directly at the sun is it has ascended too close to its zenith. The preferred times are just before sunrise up until 10:30 am, after that the suns rays can be harmful and can injure your retina. Remember a little will go a long way, and to stand before the sun with closed eyes will still allow you to partake of its beneficial energies.
