Thermal power: Use your body heat to power wearable technology

There’ll soon be no need to ever take off wearable technology as your body heat will be able to run a generator to keep it powered-up.

Thanks to a new invention by scientists in Korea heat that escapes the body can be converted into energy using the generator that can be curved along with the shape of the body.

The researchers developed the glass fabric-based thermoelectric generator to be light and flexible which could help to further commercialise wearable technology.

Byung Kin Cho, who led the team in creating the generator, said that with more development the technology could be used on a large-scale to stop heat energy not being used.

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At present wearable technology, such as the activity tracking Fitbit Flex wrist band, is developed with long-lasting battery life – the Flex has a battery life which can last up to five days.

However the latest technology would remove the need to ever take wearable technology off, which can cause some users to stop using their gadgets.

It also comes with the benefit that using thermal energy to power and recharge wearables would not need to use any energy created by non-renewable forms.

The small generator was created and tested on small bracelet and it is said it can be able to provide power in a stable and reliable way.

Cho further described how the generator could be used, he said: “Our technology presents an easy and simple way of fabricating an extremely flexible, light, and high-performance TE generator.

“We expect that this technology will find further applications in scale-up systems such as automobiles, factories, aircrafts, and vessels where we see abundant thermal energy being wasted.”

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So far only two types of thermal energy generators have been developed, these have been based on either organic or inorganic materials.

Until now the organic generators have been able to work with human skin but have not been able to generate enough power to be put to practical use.

While those made of inorganic materials have been able to generate enough power but have been too bulky to be able to be used with wearable technology.

Cho came up with the a concept and design technique to build a flexible TE generator that minimizes thermal energy loss but maximizes power output.

The new concept uses liquid like pastes of thermal electronic materials printed on to a glass fabric.

When using the generator, with a size of 10cm by 10cm, for a wearable wristband device, it will produce around 40 mW electric power based on the temperature difference of 31 °F between human skin and the surrounding air.


Images 2 and 3 courtesy of KAIST


 

A new kind of super food: How shape-shifting ingredients could help fight obesity

Obesity has turned into an epidemic that is costing millions a year in healthcare and yet it could be entirely preventable with the right diet – if only it wasn’t so difficult to cut down on the various treats we snack on during the day.

The UK’s chief medical officer has warned in a new report that obesity is increasingly regarded as the norm in the country, meaning millions of overweight people may be unaware of, or in denial about, the health risks they’re living with.

Chemical engineers at the University of Birmingham are tackling one of the main reasons why we pile on those extra pounds: excessive snacking in between meals.

The scientists have come up with an edible gel that changes the structure of food inside the stomach and could trick the brain into feeling full for longer.

They believe the gel could become an ingredient in everyday foods, for example the ubiquitous breakfast staple porridge.

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The research focuses on liquid and soft textured foods which form a large part of the modern diet. Such foods tend to be high in fat and sugars but are digested quickly, causing fluctuations in blood glucose levels and offering limited satiety.

The ability to restructure liquid and soft foods into thicker textures once they have been ingested could help slow down energy release and leave the consumer more satisfied by what they eat and less inclined to continue snacking.

Chemical engineer Jennifer Bradbeer, along with colleagues at the University of Birmingham, showed it’s possible to manipulate food once inside the stomach.

The edible gel that does the trick is extracted from two biopolymers, low acyl and high acyl gellan gum, which are derived mainly from natural sources such as seaweed, agar, starch, and citrus peel and are already used in food production to influence texture or viscosity.

“The gel works by becoming more solid when it hits an acidic stomach-like environment. It breaks down slowly, giving your brain a chance to catch on that your stomach is full,” explains Bradbeer.

Her research is based on the idea that sticking with three square meals a day – as opposed to snacking throughout – could be a route to overcoming obesity.

“If the urge to snack between meals can be reduced or eliminated using this approach, then the calorie intake, especially in the form of high fat or sugar products, can be reduced,” she says.

The idea of eating gellan gum certainly doesn’t sound very appealing, but the good news is such self-structuring gels could be delivered in foods such as porridge, soups, energy drinks and meal replacement drinks.


“We have some promising data involving human volunteers consuming self-structuring beverages.”


At this stage the gel doesn’t provide a complete solution as no energy is released to the body to complement the sensation of satiety.

The researchers are currently looking at ways to encapsulate sugars or starches that can be slowly released and digested to provide a low level of nutrition, so the food keeps both the brain and the body satisfied.

A further step is to test the gel on volunteers and translate the research into a marketable product.

“In the context of energy release, we have some promising data involving human volunteers consuming self-structuring beverages with glucose and measuring blood glucose release through the collection of blood samples,” Bradbeer explains.

It isn’t clear yet how soon the shape-shifting gel will be available as an addition to our porridge or soup. In the meantime we’ll just have to do our best to resist those snacks.