Gadre writes –

Some of the fruit and vegetables we eat can be used to make electricity. The electrolytes in many fruit and vegetables, together with electrodes made of various metals can be used to make primary cells. One of the most easily available vegetable, the ubiquitous lemon can be used to make a fruit cell together with copper and zinc electrodes. The terminal voltage produced by such a cell is about 0.9V. The amount of current produced by such a cell depends on the surface area of the electrodes in contact with the electrolyte as well as the quality/type of electrolyte.

The AVR microcontroller is a leading low power microcontroller that has been around for almost a decade now. Recently, new lower power devices have been added to the AVR family, called the PicoPower AVR microcontrollers.

In this instructable, we show how even the regular AVR devices can be set up and programmed to run off a fruit battery.

Tiny AVR Microcontroller Runs on a Fruit Battery – Link.

Lemon-Powered AVR Tiny – Link.