what do bananas, oranges, potatoes and other fruits and vegetables have in common with dry cells? Researchers from the Sri Venkateshwara University, Tirupathi, Andhra Pradesh, have developed 'biobatteries' from these natural products based on the principle that all living matter emit certain amounts of electric power. They have demonstrated that fruit and vegetable waste can substitute chemical electrolytes in batteries.

Scientist Prashant Kumar and his team conducted experiments with brinjal, cabbage, carrot, lemon, banana, potato and other vegetable and fruit waste which yielded an output ranging from 0.66 v to 0.76 v. A bio-battery made from banana waste produced electricity ranging from 1.69 to 1.97 v. Peels of various fruits and vegetables are mashed into a paste which is placed in a plastic container.After establishing the flow of microcurrent in the paste, copper-zinc electrodes are connected to the paste. The team has produced a working model of bio-batteries that can be used in electronic clocks, calculators, toys and other similar devices that need small amounts of electric current over a long period.