Are they more efficient, and if so, why aren’t they all white?
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Monocrystalline silicon is generally created by one of several methods that involve melting high-purity, semiconductor-grade silicon (only a few parts per million of impurities) and the use of a seed to initiate the formation of a continuous single crystal. This process is normally performed in an inert atmosphere, such as argon, and in an inert crucible, such as quartz, to avoid impurities that would affect the crystal uniformity.
The most common production technique is the Czochralski method, which dips a precisely oriented rod-mounted seed crystal into the molten silicon. The rod is then slowly pulled upwards and rotated simultaneously, allowing the pulled material to solidify into a monocrystalline cylindrical ingot up to 2 meters in length and weighing several hundred kilograms. Magnetic fields may also be applied to control and suppress turbulent flow, further improving the uniformity of the crystallization.[3] Other methods are zone melting, which passes a polycrystalline silicon rod through a radiofrequency heating coil that creates a localized molten zone, from which a seed crystal ingot grows, and Bridgman techniques, which move the crucible through a temperature gradient to cool it from the end of the container containing the seed.[4] The solidified ingots are then sliced into thin wafers during a process called wafering. After post-wafering processing, the wafers are ready for use in fabrication.
Compared to the casting of polycrystalline ingots, the production of monocrystalline silicon is very slow and expensive. However, the demand for mono-Si continues to rise due to the superior electronic properties—the lack of grain boundaries allows better charge carrier flow and prevents electron recombination[5]—allowing improved performance of integrated circuits and photovoltaics.
Adco wrote:The photovoltaic effect relies on a photon striking an electron to produce an emf. Therefore, the absorbing material must have "direct" contact with the incoming light and not be reflected away.
mindhack wrote:Interesting. So there’s no way around in the case of colour at least, but what else can be done to prevent the panels from becoming too hot?
Surrounding them with plant material, like grass or moss, that could work. I don’t see that anywhere. Probably too tricky on rooftops, but why not integrate green in solar fields?
Oh and another thing. I saw a nature documentary once, about giraffes (made by the one and only famous Dave) Amazingly giraffes keep their skin cool because how it is coloured. The dark spots warm faster than the lighter stripes, which causes a cooling airflow. I thought it brilliant design
Perhaps solar panels can’t be white then, but what if they’d resemble a giraffe’s skin?
Spearthrower wrote:mindhack wrote:Interesting. So there’s no way around in the case of colour at least, but what else can be done to prevent the panels from becoming too hot?
Surrounding them with plant material, like grass or moss, that could work. I don’t see that anywhere. Probably too tricky on rooftops, but why not integrate green in solar fields?
Oh and another thing. I saw a nature documentary once, about giraffes (made by the one and only famous Dave) Amazingly giraffes keep their skin cool because how it is coloured. The dark spots warm faster than the lighter stripes, which causes a cooling airflow. I thought it brilliant design
Perhaps solar panels can’t be white then, but what if they’d resemble a giraffe’s skin?
My only consideration here is how difficult it might be to get giraffes onto your roof.
Any addition of a reflecting colour would decrease the efficiency of the panel.mindhack wrote:Interesting. So there’s no way around in the case of colour at least, but what else can be done to prevent the panels from becoming too hot?
Surrounding them with plant material, like grass or moss, that could work. I don’t see that anywhere. Probably too tricky on rooftops, but why not integrate green in solar fields?
Oh and another thing. I saw a nature documentary once, about giraffes (made by the one and only famous Dave) Amazingly giraffes keep their skin cool because how it is coloured. The dark spots warm faster than the lighter stripes, which causes a cooling airflow. I thought it brilliant design
Perhaps solar panels can’t be white then, but what if they’d resemble a giraffe’s skin?
mindhack wrote:So Adco, others, you don’t think I’m brilliant with my novel giraffe idea, eh?
mindhack wrote:Interesting. So there’s no way around in the case of colour at least, but what else can be done to prevent the panels from becoming too hot?
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