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Comments: 366 +- Idle: Teenager Invents Cheap Solar Panel From Human Hair on Wednesday September 09, @11:59AM
Posted
by
samzenpus
on Wednesday September 09, @11:59AM
from the 50-watt-shampoo dept.
from the 50-watt-shampoo dept.
background: url(//a.fsdn.com/sd/firehose/005/843/353-1-thumb.png); width:130px; height:97px;
power
Renoise writes "Milan Karki, 18, who comes from a village in rural Nepal, believes he has found the solution to the developing world's energy needs. A solar panel made from human hair. The hair replaces silicon, a pricey component typically used in solar panels, and means the panels can be produced at a low cost for those with no access to power. The solar panel, which produces 9 volts (18 watts) of energy, costs around $38 US (£23) to make from raw materials. Gentlemen, start your beards. The future of hair farming is here!"
Shaw's Principle:
Build a system that even a fool can use, and only a fool will
want to use it.
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It's green... (Score:2)
to get a haircut!
Re: (Score:2)
Re: (Score:3, Insightful)
Re: (Score:3, Insightful)
It's free for the taking because as of yet there is no value to freshly cut hair (unless it's long enough to make a wig out of). Even though this article has an overwhelming stench of bullshit, if it were true and human hair became an energy source, the price of that hair would rise dramatically. "Goldilocks" would take on a whole new meaning...
Re: (Score:2)
as the reply says, barbershops have an excess of hair that already goes to other philanthropic/charitable interests, so getting some is easier to come by than what you are almost positive of. Lets just say wig shops aren't exactly in a shortage.
You insensitive clods! (Score:5, Funny)
Shampoo? (Score:2)
So in future, we'll use shampoo that maximizes the energy production of our hair?
Someone Had Too (Score:4, Funny)
Like all technology this will be hair today and gone tomarrow
*I'll be here all week folks!
Neat (Score:3, Funny)
Re: (Score:2, Funny)
You can't call them "bearded ladies" any more they prefer "Italian American" now.
Everyday (Score:3, Insightful)
The world gets a little weirder...
Re: (Score:3, Insightful)
Scams are older than the human species.
The world doesn't get weirder, although I wonder if it gets more gullible...
I think there is a 9V battery in that contraption, going by voltage reader.
Re:Everyday - Scams (Score:5, Insightful)
That's what I thought too.
The chances of this being both real AND viable if developed in the best labs of Japan, Germany, Korea, or the US would be slim to none.
The chances of being developed by a kid from a village with no electricity are astronomically small. (Here is where I get modded troll for showing a western bias. So be it.)
Everybody up-thread is debating ohm's law and assorted fine points while failing to notice the 800 pound gorilla looking over their shoulder. Do these people thing materials research would have missed this attribute of hair? These things are not done by chance any more like Edison tinkering in his lab and jerking whiskers out of a passing cat trying to develop a filament for a light bulb. You need a material that has certain properties, you key it into the computer and out pops all the candidates, the good, the bad, and the ridiculous, all rated on any number of scales you wish.
A little skepticism goes a long way.
Parent
Re:Everyday - Scams (Score:4, Interesting)
* Most materials haven't had any meaningful measurements made for any property that is actually interesting.
* Most measurements are crap. Many published measurements are crap. The amount of practice and control necessary to make useful measurements is outlandish.
* Published data for any but the most lavishly studied materials range wildly. What's the vapor pressure of, for example, RDX at STP. Checking the published sources, you'll find answers ranging over 6 orders of magnitude. So, ..., where does "somewhere between 1 millisquat and 1 nanosquat" fall on this sorted list?
This idea that there's a giant database of materials properties that contains accurate and precise data for all technologically interesting properties of most materials is bunk.
And then, ..., what's hair? Since when did hair become a specific material? Thick hair? Thin hair? Oily hair? Dry hair? Which property were you asking about? Is the hair split? Follicle attached? Old and dessicated? New and slightly less dessicated?
Yes, I think the claim made in the article is bunk. And I bet no one here can provide a single (real) citation to a source for the current-voltage relationship for hair.
Parent
Re: (Score:2)
This doesn't seem weird to me at all. I mean, if we can use our excrement for fuel for some form of power, why not use other things from our body that we generally don't have a use for?? Sounds more like a logical step, to me.
Why don't people with ponytails (Score:2)
get electrocuted when they go outside?
Re:Why don't people with ponytails (Score:4, Funny)
Their dry leather sandals prevent current flow to ground and if it's damp, the decreased resistance to ground merely lets the current drain away at a safe rate.
Your homework is to determine the capacitance and inductance of RMS, and at what frequency he would resonate.
Parent
Re: (Score:3, Insightful)
Honestly, I think people who associated "short hair = manly" (after wars of XIX and first half of XX century, where shaving was an effective way of supressing diseases without access to sanitation; when millions of young, shawed pawns in hands of rulers were coming back they suddenly became hero veterans...just for being pawns) should mind their own business.
Really, I can't believe how so many woman were scammed into this "model" of manhood - one that disguises poor personal hygiene, diseases and genetic di
Re: (Score:3)
1) They are a priority. A species that doesn't select for them, doesn't survive long. Where you might misunderstand me is in having the impression that I suggest health, and even healthy hair, is all that matters - nonsence, I said no such thing. I'm simply amazed at the fact that current sexual selection in western societies promotes (among other things!!!) traits that are advantegous only to small group of unhealthy males. It's against the interests of females, it's against the interests of large group of
India (Score:3, Interesting)
Melanin as a semiconductor (Score:5, Informative)
Turns out that Melanin is a semiconductor. Here are some references:
- http://www.organicsemiconductors.com/ [organicsem...uctors.com]
- https://www.researchgate.net/publication/16014151_Semiconductor_properties_of_natural_melanins [researchgate.net]
While this may not be a solution for everyone, even small scale manufacture could be enough to spur research to improvement of the technology. Maybe the wool industry should start investing in this?
Ridiculous! (Score:5, Insightful)
This is really ridiculous.
The pictures show a few strands of hair. A few questions come to mind:
(1) Hair is not conductive. How can hair produce electricity if it can't conduct electrons worth a darn?
(2) Hair is not polarized-- it's the same all the way through and throughout its length. How can there be any potential difference set up across something uniform?
(3) The amount of hair shown captures maybe 0.1 cm^2 of sunlight. Even if it had 100% efficiency, that would only be 1/100th of one watt. How could it be lighting up a 5-watt fluorescent lamp with that?
Everything about this story sounds major-league bogus.
Can anyone duplicate this? (Score:3, Insightful)
Polar Bear Hair? (Score:3, Informative)
"Polar bear hair may be a natural fiber-optic cable. A cross section (right) shows a solid shaft surrounding a reticulated core. The shaft apparently can trap ultraviolet light and aim it toward the skin (above)."
"Grojean believes the hair shaft somehow conducts scattered radiation to the surface of the skin (which is
Re:Ridiculous! (Score:4, Informative)
>Someone pointed out above that melanin is actually a known semi-conductor.
Yes, and someone also said that saw palmetto cures cancer.
Just because something is a semiconductor does not mean it's like, a *semiconductor*. Horse droppings are a semiconductor.
Your typical usable-for-electronics semiconductor has an impurity level of like one part per billion. It ceases to be interesting if the impurity level get much higher than this.
Please posit how this kid has purified melanin to one part per billion, then doped it with the right miniscule proportion of carriers.
Then we can talk about semiconductors.
Parent
well, as Borat said..... (Score:3, Insightful)
.....We can at last import energy from kazhakistan!!!!!! [youtube.com]
Dilemmas! (Score:4, Insightful)
I'd like free electricity, but I really hoped to write a successful computer language some day. What to do?
I think (Score:5, Funny)
this article was either posted 161 days too late, or 204 days too early. Not certain which.
Re: (Score:2)
I don't think the original article suggests they are the same, although it does seem surprising if this thing can produce 2A.
Re: (Score:3, Funny)
I don't think the original article suggests they are the same, although it does seem surprising if this thing can produce 2A.
If it produces 9V, I would not be the least surprised if it puts out 2A across 4.5 Ohms resistance.
Re:9V != 18W (Score:5, Informative)
The same principle applies to any other non-ideal voltage source. A solar panel that produces 9V open circuit or at some low current is not necessarily able to produce 9V at 2A.
Parent
Re:9V != 18W (Score:5, Insightful)
The conductivity of hair is very low. I know this because I have inadvertently applied 600 V between 3/4" of hair and my (thankfully dry and unsweaty) skull, yet I live to type about it. The possibility of a hair solar cell is, in my oh-so-humble opinion, exceedingly unlikely.
However, I was [for once] inspired to RTFA.
Parent
Re:9V != 18W (Score:4, Informative)
he solar panel, which produces 9 volts (18 watts) of energy, costs around $38 US (£23) to make from raw materials.
That is raging bullshit.
9V at 18 watts = 2 AMPS at 9 volts. The teenager is lying, the summary is lying, or whole thing is fake.
so this kid stumbled upon a cheap system that is 900X more efficient than the best Solar panels made by industry? either that or his solar panel is 30 feet long by 2 feet wide.
Parent
Re: (Score:2)
The 'active ingredient' is the melanin in hair. The catch is, this degrades over the period of a few months, not a few years. This is the reason why the price can be so low - there's a hidden 'cost' in lifespan.
Re: (Score:3, Informative)
From TFA:
Half a kilo of hair can be bought for only 16p in Nepal and lasts a few months, whereas a pack of batteries would cost 50p and last a few nights.
So, no it's not a hidden cost, it's just cheaper than the existing costs.
Re:9V != 18W (Score:4, Funny)
Only breathing every two months?
God man, i can barely last 2 minutes...
Well, here i go... huuuuuuuuuuuup
Parent
Re:9V != 18W (Score:5, Informative)
Not sure how you've worked that out. At a fairly optimistic 10% efficiency, I reckon he would need about a fifth of a square meter to output 18W, given that sunlight has an energy density of 1kW/m^2, give or take. That roughly matches area of the device he's shown holding. A 30ftx2ft similar panel would have roughly 600W output.
This doesn't mean it's not bullshit, naturally; it just means that the numbers *could* add up.
Parent
Re: (Score:3, Insightful)
It is barely possible that he kluged up something that puts out 9 volts into the extremely high impedence of a digital voltmeter. The rest is bullshit, perhaps originated by the same doofus who thinks that a watt is a unit of energy.
Re:9V != 18W (Score:4, Funny)
This is nothing. I once created the Ultimate Pleasure Device from 2 bottles of cheap wine, 10 ounces of ground beef (lean) and and a 12" piece of PVC tubing.
Parent
Re:9V != 18W (Score:5, Funny)
But what did you do with the other 9" of the PVC tubing?
-
Parent
Re:9V != 18W (Score:4, Interesting)
True, this is false.
There's a picture of a multimeter, and a lighted bulb, but the panel shown is IN THE DARK! Unless it's on a totally different panel that is in the sun, it's way fake. And, as pointed out, 9volts is trivial, but 18 watts is actually really hard.
Also, the reporter is not energy-literate, but that's not a surprise.
I once showed an artist a calculator running on a lemon battery. Not knowing about CURRENT and POWER, she then went and proposed a project to a museum where a classic Gameboy would run on lemons, and they accepted it. Of course this would take a few thousand lemons! Luckily, it was an art museum, not a science museum. We ended up hiding double-A's inside some of the lemons. (We came clean to anyone smart enough to ask!)
I suspect similar shenanigans...
Parent
Re: (Score:3, Funny)
True, this is false.
There's a picture of a multimeter, and a lighted bulb, but the panel shown is IN THE DARK! Unless it's on a totally different panel that is in the sun, it's way fake. And, as pointed out, 9volts is trivial, but 18 watts is actually really hard.
Also, the reporter is not energy-literate, but that's not a surprise.
I once showed an artist a calculator running on a lemon battery. Not knowing about CURRENT and POWER, she then went and proposed a project to a museum where a classic Gameboy would run on lemons, and they accepted it. Of course this would take a few thousand lemons! Luckily, it was an art museum, not a science museum. We ended up hiding double-A's inside some of the lemons. (We came clean to anyone smart enough to ask!)
I suspect similar shenanigans...
The REAL question is... did you get some?
Re: (Score:3, Funny)
Re: (Score:3, Insightful)
Re: (Score:3, Insightful)
Re: (Score:3, Informative)
Voltage is not the same as power.
Umm, yes it is. What's next, are you going to say you can borrow yourself out of debt?
Voltage is electromotive potential. It measures a sort of pressure that occurs on electric charge. Current is measured in amps and measures the flow of charge itself. You can't have power (watts) without current. So, no, voltage is not the same as power.
Re: (Score:3, Funny)
There's no getting around Ohm's law...
Ha! I see that the Electric Police Force (aka The Faraday Fuzz) aren't nearly as corruptible as they around around here. A Benjamin or two to grease the wheels of Electric Justice, and they'll turn a blind eye to just about anything.
Hell, the other day I was running 100A through a 1k ohm load off a 9V battery, and my local Electric Police Officer just gave me a knowing smile and a tip of the hat before carrying on his merry way.
I heard down in Mexico you can do pret
Re:And I just shaved my head!!! (Score:4, Funny)
I got drunk with my Dad and Uncle last week and we shaved our heads, now everywhere I look someone is rubbing in the fact I don't have hair anymore!!!! Like OMG!!!
So, how's life in your trailer park?
Parent
Re: (Score:3, Insightful)
It's an incomplete story. What we need to know to evaluate cost is A. life expectancy, and B. W/m^2. A solar panel that produces the same wattage for a price comparable to some of the higher density solar panels (IIRC) is cool if it lasts at least as long and has similar density. Otherwise, the replacement costs or the shipping costs and installation footprint make it more expensive, respectively.
Re: (Score:3, Insightful)
Careful you don't nick the plastic with the razor or all of the air will escape.