24-April-2020 By Jeffrey Cooper

Energy Harvesting: Sweat

It was with some excitement that I read this article this week about harvesting energy from sweat, using it as fuel to power a fuel cell. This skin-thin sensor incorporates electronics and a radio and can operate for up to 60 hours!

While this is obviously a temporary patch, due to its fragility, I am hopeful that it could be incorporated into other wearables that can use the extra energy to top off the battery. It can also be used to provide auxiliary sensors to provide data from other areas of the body (such as blood sugar) during a run, while leaving the power-hungry GPS functions to the smart watch itself. If the patch was durable enough, it could potentially be used for weeks at a time, activating when you worked out and sweat.

In the healthcare market, it would find immediate utility as a biosensor for various conditions such as diabetes and sport applications such as hydration and glucose and lactate levels. It won’t need to continuously transmit because the chemical gradients change at a slow rate compared to other types of sensors, such as accelerometers.

Check out the full (fairly technical) article at https://robotics.sciencemag.org/content/5/41/eaaz7946.full. It sounds like it could be relatively straightforward to manufacture as it doesn’t appear to contain exoctic ingredients. Maybe someday soon we’ll have these available as options for those in need of better medical monitoring and those very serious about their sport.