Solar Water Heater from Brazil "Soda bottle solar water heater" -Panasonic ecoideasnet

This self-built solar water heater is made of plastic bottles, black painted milk cartons and PVC pipes. It is popular in southern Brazil.

The water is heated passively by solar energy. As the hot water rises, it is naturally replaced by cold water, so no pump is needed.

 

CCTV-9 report: Solar bottle lights in the Philippines

Video report of an ingenuous low-tech solar-tube design being used in the Phillipines.  It lets poor Filipino's light their homes during the day while using zero electricity or burning fuel.