Teen Invents Flashlight That Could Change The World

[TerraHertz]

I didn't see this mentioned here, but it should be. Apologies if it was and I missed it.

http://news.yahoo.com/blogs/this-could-be-big-abc-news/teen-invents-flashlight-could-change-world-182121097.html
Teen Invents Flashlight That Could Change The World
February 25, 2014

Thermal gradient between body heat (hand) and room temperature --> peltier cells --> power conversion circuit --> LEDs.
Really clever idea.

Both parents are ham radio operators. Plus she's cute too. Why isn't she a member of this forum?

[ataradov]

Was not this a story last year?

I personally don't see how it could change anything. Somehow this got promoted out of 100's cool projects that are done each year.

[Psi]

I wonder how much energy you could harvest from a sleeping bag lined with hundreds of tiny flexible peltier cells.

Recharge your phone while you sleep!

[ataradov]

Here is the same story from June 2013 - http://www.extremetech.com/extreme/160003-15-year-old-girl-invents-flashlight-powered-by-the-heat-of-your-hand.

[zapta]

>> Teen Invents Flashlight That Could Change The World

The human race just left the Before The Flashlight  era and entered the After The Flashlight era. Life will not be the same. Expect big changes here at eevblog.

[mariush]

This is stupid, just making an article out of something not really special. I may sound racist but I'd bet if the girl was Chinese or not perfectly white and beautiful with nice teeth and all that, nobody would even write an article about it.

I mean, everyone thought about it, but probably nobody did this before of the poor conversion efficiency and lack of very high efficiency leds.

We have something very similar for years now ..... a coil of wire, a permanent magnet, a capacitor or supercapacitor , a bunch of leds.. shake the flashlight and you have light. I bet it's also cheaper than peltier elements and it would also work better in all kinds of weather.. for example in winters when you go outside and your hands are in gloves or very gold.

[6E5]

What if you live in the Arctic and it's -30? Even if you had any substantial body heat radiating, who has bare hands in that type of weather? This is not something new, it's basically a thermocouple connected to a light bulb... Been around for 100 years.

[Kjelt]

Well I like the idea but this is probably more efficient and effective and proved itself here in WW2: http://en.wikipedia.org/wiki/Mechanically_powered_flashlight
Still the combination of Peltier elements and the human body could have more interesting uses.

[amyk]

We have something very similar for years now ..... a coil of wire, a permanent magnet, a capacitor or supercapacitor , a bunch of leds.. shake the flashlight and you have light. I bet it's also cheaper than peltier elements and it would also work better in all kinds of weather.. for example in winters when you go outside and your hands are in gloves or very gold.

I don't know, maybe these "thermal flashlights" will start showing up all over Alibaba as novelty items (just like those "bladeless" fan things), just like the shake ones.

Except these will stop working once the whole thing is uniformly warmed up to the same temperature, and they will just not work in extremely hot climates.

[free_electron]

Add a little harvester circuit and a coin cell liion and you would not have to hold it all the time. Plus, knce charged you can get more brightness. Linear tech has harvesters that work from 0.3 volt ...

[Rufus]

Here is the same story from June 2013 - http://www.extremetech.com/extreme/160003-15-year-old-girl-invents-flashlight-powered-by-the-heat-of-your-hand.

Where she says "and I needed only 0.5mW to obtain a good usable LED brightness".

Wonder what they would say about that on the candle power forums.

[tom66]

0.5mW is adequate for an indicator, but you're not going to see much with it.

[rexxar]

I don't see what's so special about this. It's an expensive, inefficient, almost unusably dim flashlight. How is this better than the shake flashlights, or the ones with cranks, or other mechanical power? I've had cheap flashlights where you pull a lever that spins a motor that just dumps charge into a NiCad pack. At least with a mechanical type system you can ALWAYS get some sort of use. Like said before, once the whole device warms up, or if it's hot outside, the thing won't work.

[ataradov]

If you have no useful hands then that makes the shake ones a bit impossible.

Shake ones can be charged by shaking and then used normally. Otherwise you won't be able to use it anyway, because who needs a flashlight that is shaking like crazy?

This one is not very useful without at least one hand either.

[Zero999]

What if you live in the Arctic and it's -30? Even if you had any substantial body heat radiating, who has bare hands in that type of weather?

Well, the lower the ambient temperature, the more efficient it'll be but I know what you mean.

I wonder how much energy you could harvest from a sleeping bag lined with hundreds of tiny flexible peltier cells.

Recharge your phone while you sleep!

For any decent amount of power, the sleeping bag will have to leak a lot of body heat so will feel cold.

[zapta]

This is stupid, just making an article out of something not really special. I may sound racist but I'd bet if the girl was Chinese or not perfectly white and beautiful with nice teeth and all that, nobody would even write an article about it.

Yes, you sound racist but it does not mean that you are not right ;-)

This story is on the nexus of women in engineering/sciences and sustainable/green energy.  Both are politically correct themes so no surprise it got published. Contrast this with more influential achievements like fracking by oil corporations run by older greedy white males.

[peter.mitchell]

Add a little harvester circuit and a coin cell liion and you would not have to hold it all the time. Plus, knce charged you can get more brightness. Linear tech has harvesters that work from 0.3 volt ...

I was thinking one of the LT harvesters, super cap and peltier, whilst coin cells are great, if you want to add say a strobe mode for signalling a rescue vehicle, i don't think the coin cell could handle the current.

[grumpydoc]

One thing I noticed from the text on the Yahoo site (I'm not allowed to watch the video, apparently) was this

"At roughly 24 lumens, Ann’s flashlight’s brightness falls shy of commercial flashlights, which output dozens if not hundreds of lumens."

At 24 lumens for 0.5mW of power that's 48000 lumens per watt

So it might be somewhat ground breaking as I that seems to be well above 100% efficiency.

Or not, as the case might be

Kudos to her anyway if she had the idea for herself and turned it into a practical design - more than most 15 year olds would manage.

[EEVblog]

This story is on the nexus of women in engineering/sciences and sustainable/green energy.  Both are politically correct themes so no surprise it got published.

Yes, welcome to the world of the media. You need angles to make stories people want to read, or what publishers think people want to read. This one has several angles:
1) It's a girl doing technology
2) It's a young girl
3) It's a cute girl
4) It's save the world blah-blah

It ticks all the boxes.
The only way it could get better is if she was a deaf mute amputee, or a refugee from some poor village in Africa or something.

Unfortunately this is how the world of the media works. Stories are stories because they either have out-of-the-ordinary angles to them, or a combination enough to make it appear interesting to the punters.

[saturation]

Flashlights in non-emergency situations are best still battery powered for sheer lumen/watt output, such as security guards, searchlights etc.,

For emergency use, the last thing you need is something that will steal heat away from you.  Even in temperate climates, protection from cold is important.  The bodies first response in emergencies is to sap heat from your extremities to conserve it in your core, so charging something by holding it would take a long time, if at all.  A more useful thing if you were in a bind in a terrestrial condition would be power generated from walking [ electromechanical transducer in your shoes, many such designs].  In ocean emergencies it would be solar power; combine them both for an ultimate emergency power source and back it all up with a crank generator in a MILSPEC water and shock proof case.

[Stonent]

This is stupid, just making an article out of something not really special. I may sound racist but I'd bet if the girl was Chinese or not perfectly white and beautiful with nice teeth and all that, nobody would even write an article about it.

Yes, you sound racist but it does not mean that you are not right ;-)

This story is on the nexus of women in engineering/sciences and sustainable/green energy.  Both are politically correct themes so no surprise it got published. Contrast this with more influential achievements like fracking by oil corporations run by older greedy white males.

Her mom was from the Philippines and her dad appeared to be eastern European. So not fully white.

As far as fracking goes, it's been around a lot longer than the past few years, but suddenly it's the bogey man.

[NiHaoMike]

For emergency use, the last thing you need is something that will steal heat away from you.  Even in temperate climates, protection from cold is important.  The bodies first response in emergencies is to sap heat from your extremities to conserve it in your core, so charging something by holding it would take a long time, if at all.

A very large percentage of Americans have plenty of "excess energy" that would be better used than stored.

[Macbeth]

This is stupid, just making an article out of something not really special. I may sound racist but I'd bet if the girl was Chinese or not perfectly white and beautiful with nice teeth and all that, nobody would even write an article about it.

She's half Filipino. Pretty darned close to China.

[calexanian]

Dave nailed it! Big picture here guys. Wouldn't you prefer living in a world where every teenager understood how a peltier device, and led, and how some physics work? All you have to do is find that first little step for a kid to get I to the world of REAL science and technology for them to look at the world differently and know everything has a explanation and obeys the laws of physics. We need more of that. What were your projects like at that age? Most of mine involved 9 volt batteries, relays, and capacitors to do simple things is very inefecient ways.

[6E5]

What if you live in the Arctic and it's -30? Even if you had any substantial body heat radiating, who has bare hands in that type of weather?

Well, the lower the ambient temperature, the more efficient it'll be but I know what you mean.

I wonder how much energy you could harvest from a sleeping bag lined with hundreds of tiny flexible peltier cells.

Recharge your phone while you sleep!

For any decent amount of power, the sleeping bag will have to leak a lot of body heat so will feel cold.

Sorry, I made a terrible example. As you guessed, I was thinking about a situation where you had to wear insulating gloves.