Solar panels embedded in clothes charge a mobile phone

Clothing embedded with tiny solar cells the size of a flea will allow wearers to generate electricity on the move and charge items like mobile phones and smartwatches.
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The cells are encapsulated in a resin which allows the textile fabric to be washed and worn like any other form of clothing. Measuring only three millimetres in length and 1.5 millimetres in width, the cells are almost invisible to the naked eye and cannot be felt by the wearer. For all intents and purposes, garments appear exactly the same as any other form of clothing despite having the capability to generate electricity

5 IoT Energy-Harvesting Options

New energy-harvesting technologies coupled with energy-efficient battery storage and low-power platforms have pushed the boundaries of where embedded systems, IoT, and edge devices can be utilized.

https://www.electronicdesign.com/power/these-5-iot-energy-harvesting-options-stand-out-field

This article, in Electronic Design,  provides snapshots of some of the latest technologies that allow those devices to siphon energy from their surroundings for operation in remote areas.

Whatever the application, all electronic devices require power of some sort, and energy harvesting is already allowing them to operate in a standalone manner, reducing managing costs and maintenance time in the field.