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MIT Unveils Sun-Free Photovoltaics
An anonymous reader writes "Researchers at MIT just unveiled a new solar power generator that doesn't need sunlight to function. The button-sized power generator can tap energy from heat, the sun's rays, a hydrocarbon fuel, or a decaying radioisotope, and it can run three times longer than a lithium-ion battery of the same weight. It is hoped that the technology may one day be used to generate power for spacecraft on long-term missions where sunlight may not be available."
We use this thing to run a space heater, which in turn heats up the generator and provides even more energy. Bingo, we've got an endless energy supply. String a bunch of these puppies together and goodbye fossil fuels!
You're welcome, world.
SJW: Someone who has run out of real oppression, and has to fake it.
I want one for my laptop. At last I'll be able to surf continuously.
Can I put this on my walls in the summer and actually get energy from cooling my house down?
The button-sized power generator can tap energy from heat, the sun's rays, a hydrocarbon fuel, or a decaying radioisotope.
Looking at TFA, it looks like it takes heat, converts it to light in very specific frequencies, and then uses that to generate electricity. So, any source of heat whatsoever should theoretically be able to power these. We already possess thermoelectric generators, but they tend to be effective only at very specific and fairly low temperatures. Potentially, this kind of technology could replace conventional turbines in most power plants (nuclear, coal, et al. Basically, any that directly generate heat). Anyone know what kind of efficiencies these could operate at vs. steam turbines? I know turbines are fairly efficient (but large, hence this new tech), but it seems like these could (maybe) exceed those.
Also, if these things could be designed to require fairly low heat, then I imagine they could be used in basically any everyday device, generating low power from room-temperature heat. They don't seem to require the heat-differential of thermo-electric generators, so I wonder if they could supplement/ replace batteries in many daily electronic devices (pacemakers and hearing-aids come to mind, cell phones likely require way to much power). Anyone know if that kind of thing is at all practical?
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
So, Can I combine it with a battery and then use it as a heat sink for the CPU in my phone?
I only need juice until it gets hot, right?
/me sips his coffee and ponders a new sig...
Comparing this device to a battery is like comparing a gas tank to a an electric motor. A battery stores energy, while this converts it to another form.
How much more power does it produce than a solar panel of the same weight?
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
I am simply stunned that nobody has mentioned body heat. Think about it, all you would need to do to charge your cell-phone is put it in your pocket! Spelunking? Attach a patch to your arm and your light lasts even if you (idiotically) run out of batteries. The applications for this tech are endless, and quite frankly, the article criminally neglects this fact.
Boredom is bliss.
What does "runs three times longer than a battery of same weight" even mean?
The generator runs as long as there is radiation around it, no?
I've clicked on everything I can see, and I don't see the actual efficiency rating they keep alluding to.
Those clever Germans have already mastered solar power without the sun.
http://bishophill.squarespace.com/blog/2010/4/13/its-true.html
Hoopty Fucking Doo
are in a square foot?
If video games influenced behavior the Pac Man generation would be eating pills and running away from their problems.
I suspect the Carnot cycle is a valid predictor for the potential efficiency of this type of device. Even though that may be the case, this is an interesting device. It appears to be a possible way to fulfill the role of a fuel cell without the fuel cell's sensitivity to fuel quality.
Implement this into the road system and you'll solve the energy crisis! You could probably power half the US with the amount of heat being generated on Texas roads today! /dnrtfa
This machine transforms heat into work. It could be used to reverse entrophy! Take that, thermodynamics!
I rarely respond to comments. Also, don't ask for clarifications: a brain and Google are faster, believe me!
I had this idea like 5 years ago. But, being a mathematician, I merely discovered the existence of the idea. These engineers have only supplied an example implementation of the idea.
Trivial, trivial.
(sarcasm)
PS: I don't reply to ACs.
How old are thermocouples? Seriously folks, that someone took heat energy and created a current flow is no reason to go ga ga. Look at efficiency. Carnot heat engine is quite abstract and no matter what, there is an absolute maximum efficiency given the temperature of the source and the sink. Unless you have a bottomless pit of of sink at absolute zero degree kelvin, this sucker too would look very much like a thermocouple. Curious, interesting, might find some application in some weird situations. But in general, if ain't gonna replace either the IC engine or the battery any time soon.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
How low are the power demands of a pacemaker in terms of the Library of Congress?
i'd hit it so hard, if you pulled me out you'd be the king of britain [bash.org]
We will need Tesla Towers with giant electrodes. And transformers, many transformers, to step the voltage down from lightning to household...
Nice little gizmo I admit. Hope it turns out to actually be useful (or lead to something that is) For those who want to make a free energy device: You know people, science concluded a long time ago that you can not make more energy from nothing. If it was that simple it would have been done a long time ago. You imply that if I had lightbulb 1 and solar panel 1 in a room, then there was a wire running to another room running lightbulb 2 which shined on panel 2.. which in turn had a wire back to 1 that the energy created would be able to sustain enough power to keep each light running indefinately...... please dont say yes. It will not happen, Wires have resistance and lose energy, and solar panels are not 100% efficient at converting light to energy (nothing has a pure 100% conversion rate, light, heat, electrical, wind, etc..). If it is not 100% efficient then it will lose energy and eventually die, on top of that if it were 100% efficient you couldn't bebefit from it because all the energy involved would then be dedicated to keeping the system going, hence you would need a system that creates energy from nothing to even be slightly beneficial - impossible. I find that most people that seriously believe that it is possble are first semester college students or hippies that read one basic physics book and somehow missed the part above (or couldnt comprehend it).... and get wild impossible idea that thousands of scientits have already disproved. could we drop this idea and try something else less annoying? Maybe wait until a scientist (not you) discovers how to harness something like dark enery / dark matter - if it exists - and use it for energy.
You know, once all units are freely convertible into standard federal LOCs, google is going to divide by zero and trigger the singularity.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
The reason we use steam turbines as the mechanical step, no matter what the originating heat (fossil fuel, nuclear decay, solar, etc.) is because the phase change from liquid to vapor for water is such a huge volumetric difference that it is extraordinarily efficient for energy conversion. Photovoltaics, even these new ones, will never be as efficient in energy conversion if it tries to skip the mechanical step.
There's a reason that many energy storage systems employ molten salt or making ice during off peak hours. It make sense to use phase transitions of materials as the energy conversion step.
http://www.youtube.com/watch?v=vWxZm8WjlI8
Have gnu, will travel.
It's unlikely to replace current electricity generators but it could be a good supplement. Something that converts ambient heat to electricity could be used to...
- extract that bit more electricity from the exhaust of steam turbines and engines (ex. electric hybrid cars).
- extend battery life of devices that get hot (ex. laptops (though good laptops run fairly cool anyway)).
- be used to cool things down for "free" (if we can make them efficient enough). Uses: fridge walls, aircons, solar panel coolers, etc.
This sort of thing could be a very useful supplemental technology. I couldn't find in the articles how efficient they are. Anyone know?
Seems to me that if you're on a spacecraft and you don't have some sort of nuclear power plant, you're in trouble. Or should I be thinking "probes" here?