Purify Water used Solar Bottle

This solar bottle was invented by Alberto Medo and Francisco Gomez Paz, took an idea from Solar Water Disinfection system at Milan's International Furniture Fair and were inspired by this effective but inexpensive method of purifying household drinking water.

This bottle work when water is filled into transparent PET bottles and exposed to six hours of sunlight, the UV-A radiation and increased temperature from the solar energy will effectively kill disease-causing pathogens in the water.

Although this invention look so impressive, but how about its price,it's affordable for people around the world who have meager-to-almost-nil supply of safe drinking water, or third class countries?

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