This experiment was conducted by Haim Rabinovitch, professor of science and agriculture. He took potato quarters and placed them between copper cathode and zinc anode, which were connected with wire. He found out that these units can light a room with LED light for up to 40 days.
This information is very useful, especially to the parts in the world where technology is not so develop. This discovery gives them very opportunities and possibilities.
But you wonder why potatoes and no other vegetables? Well there are two reasons why. First, potatoes can grow anywhere in the world, in every possible climate and second you can find them everywhere.