The hair replaces silicon, a pricey component typically used in solar panels, and means the panels can be produced at a low cost for those with no access to power, he explained....The solar panel, which produces 9 V (18 W) of energy, costs around £23 to make from raw materials.But if they were mass-produced, Milan says they could be sold for less than half that price, which could make them a quarter of the price of those already on the market.
Melanin, a pigment that gives hair its colour, is light sensitive and also acts as a type of conductor. Because hair is far cheaper than silicon the appliance is less costly.
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