Feeling extra sweaty from a summer heat wave? Don’t
worry—not all your perspiration has to go to waste. In a paper
publishing July 13 in the journal Joule, researchers have developed
a new device that harvests energy from the sweat on—of all
places—your fingertips. To date, the device is the most efficient
on-body energy harvester ever invented, producing 300 millijoules
(mJ) of energy per square centimeter without any mechanical energy
input during a 10-hour sleep and an additional 30 mJ of energy with
a single press of a finger. The authors say the device represents a
significant step forward for self-sustainable wearable
electronics.