Woman prepares to go for a run wearing a smartwatch


Good things come to those who sweat

Tech > Good things come to those who sweat

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Japanese scientists have found a new technology that lets smartwatch users power their gadgets with sweat.

13 July 2021, 5:25 PM


Wearable tech has been around for decades, encouraging us to exercise and keep a close eye on our health, and even allowing us to check our texts on the go. But can it really generate electric power from chemicals in our sweat? The answer is yes!

By taking advantage of the sweat we produce, we could be looking at a more environmentally friendly way of powering devices that usually rely on batteries. So that means our own bodies can produce a near-guaranteed source of energy – check us out!

We love our wearable tech, but we always want it to do more... For a long time, those developing wearable tech have looked for an energy source that satisfies our power demands without compromising on size, and it looks like they might have finally found it.

The biggest complaint for years has been, ‘I want a longer battery life’, but bigger batteries add bulk and weight.

Let’s dive in…

Our bodies can create a source of biofuel energy – any fuel that comes from a plant or animal material – and in Japan, scientists have successfully tested a biofuel cell set up that generates electric power from chemicals in our sweat. These biofuel cells could offer high power performance in a more practical, wearable form.

After all, sweat isn’t just water. It contains small amounts of lots of minerals and other substances like glucose and lactate. These substances, called metabolites, are created by the chemical processes that constantly go on inside living beings. Scientists are particularly interested in lactate because its concentration in sweat rises with exertion – as in, the more we sweat, the stronger the presence of lactate. Think of it a bit like a really strong blackcurrant squash…

In these sweat biofuel cells, there are a layer of enzymes that react with the lactate in sweat to create an electrical current which can therefore power your device. How cool is that! And with the majority of wearable tech users being athletic, they’ll have no problem generating their own battery power – what a great excuse to run that extra few km!

Those studying biofuel technology are super excited by this development because it can be mass produced at a low environmental and material cost.  

Prototype wearables that generate power from sweat are already being developed. So, is sweat the new form of renewable energy we’ve all been waiting for? It’s getting hot in here…

Next article: Wimbledon serving aces with recycling on the go!

Warning: may blow your mind!

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