Energy extracted from a grape is enough to power tiny sensors or transmitters, meaning that silicon chips implanted in plants or animals could derive power from their hosts.

Reported in the Journal of the American Chemical Society, the grape biofuel cell was created by Adam Heller and colleagues at the University of Texas at Austin.

It produces just 2.4 microwatts, meaning that it would take several million grapes to power a lightbulb. But that’s enough energy to power tiny silicon chips. Such chips could be stuck on plants to monitor environmental conditions.

And besides grape juice, biofuel cells could derive power from bodily fluids. They could therefore power sensors implanted for such purposes as wound monitoring to aid treatment.
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