If you are on a trip with backpack straps on your shoulder, don’t think that they are not doing any work. All the movements of your backpack strap can be put to good use, thanks to researchers who have designed a novel type of energy harvesting backpack. The pack has straps made of a piezoelectric material that can convert the mechanical strain on the straps into electrical energy that may power or recharge portable electronics. The benefit of this system is that it impeccably substitutes a currently-used material with one that generates electrical energy.

When carrying 100 pounds as much as the soldiers do and walking at 2-3 mph, simulations showed that the straps could generate 45.6 mW of power. This power output could either be used to power small electronics, or be accumulated over the duration of an excursion to be used as a weightless supplemental energy source instead of carrying extra batteries.
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