Cited research: J. Renew. Sustain. Energy 2, 033103 (2010)

Schoolchildren are routinely shown how to convert potatoes into makeshift batteries using copper and zinc electrodes. Haim Rabinowitch at the Hebrew University of Jerusalem in Israel and his colleagues now report a way to rev up the power output: by boiling the potatoes first.

Boiled or electroporated Solanum tuberosum produced a voltage up to ten times higher than raw potatoes. The authors calculate that energy production from these potatoes is five- to fiftyfold cheaper than commonly used batteries and can produce light, through LEDs (light-emitting diodes, pictured), more cheaply than kerosene lamps. Potatoes could thus provide an inexpensive way to power low-energy appliances.

The authors suggest that rupturing tissue membranes by boiling or electroporation alters the properties of the tissue sandwiched between the electrodes such that it enhances the energy-generating capabilities of the biological power cell. D.C.

Credit: A. GOLBERG, HEBREW UNIV. JERUSALEM