MIT researchers develop sun-free photovoltaics | Hacker News Reader

MIT researchers develop sun-free photovoltaics

web.mit.edu

It was this line that got me:

> Based on that technology, MIT researchers have made a button-sized power generator fueled by butane that can run three times longer than a lithium-ion battery of the same weight; the device can then be recharged instantly, just by snapping in a tiny cartridge of fresh fuel.

There seems to be tons of awesome applications for such a technology. The first one that comes to mind is electronics for camping. You could have your mp3 player for your week long backpacking trip.

On that train of thought, I wonder if the human body produces enough heat for it. Imagine a radio player that just has to touch your skin to work (after proper safety evaluations, of course).

Briefly ignoring Mark of the Beast sort of implications, this has some amazing, useful potential

Imagine what you could do with the heat that a macbook puts out.

Haha, or an old AMD processor. I was mentioning body heat because we generally ~automatically~ generate that, and provide fuel, because we're always eating and putting off body heat, unless we're really ill. It'd be (functionally) free energy.

I have often noticed at conferences groups of somewhat overweight techies, clustered around a limited number of electrical outlets, to power their laptops.

I've thought to myself, "these people have too little outlet and laptop energy, and too much energy stored in their bodies." Of course the next step should be obvious: what if we had a power adapter that could plug directly into excess body fat? Lose weight and extend your battery life! Eat all you want and work it off in a marathon unplugged session of 'Angry Birds'!

This new heat-to-electricity-pathway brings us a tiny step closer to that dream.

Photovoltaic cells need to be cooler than an incandescent light source in order to work at all, and substantially cooler to work with reasonable efficiency.

So what's wrong with 98.6?

It's the line that followed that really got me: Another device, powered by a radioisotope that steadily produces heat from radioactive decay, could generate electricity for 30 years without refueling or servicing.

If that can be made safe, we're talking about devices that are self sufficient, under any conditions. Sounds like science fiction.

Actually radioisotope-powered artificial pacemakers [1] has been used commercially for some two decades now, even if they aren't very popular.

The technology of generating electricity from heat was somewhat different, but the technicalities of making small nuclear devices safe for Joe Average to just carry around in his chest are solved.

Welcome to the future, please fasten your seatbelts :^)

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[1] http://duckduckgo.com/?q=radioisotope+artificial+pacemaker&#...

They are known as RTG's. Voyager 1 & 2 both have one.

It's irksome that they make it sound like a wicked new discovery. Sure, we don't have miniature RTG AA batteries yet, but it's hardly a new idea.

I don't remember which one, but Asimov talked about micro-nuke devices powering personal electronics in a Foundation Series book.

Any idea what the power output of these things is? I didn't see any information in the article. If they can compete with li-ion in Watts/current/whatever, consider me sold.

Seems inefficient to convert heat -> light -> electricity, though I freely admit to only having a cursory understanding here.

Imagine the data center implications of this, and the implications for refrigeration in general.

More inefficient than heat -> steam -> mechanical motion -> electricity?

Spot on.

Heat -> electricity

beats

heat -> mechanical motion -> electricity.

That being said, I've yet to find the paper on the microreactor they are using from the Microsystems Technology Lab [1] perhaps it will come out in the 2011 annual report.

One fascinating use proposed for these is to power monitoring systems for high-level radioactive waste using the heat generated by said waste.

Personally I'd love to have something I could put on my dashboard that would power a fan to circulate air through my car while it was parked in the bright sunlight.

[1] http://www-mtl.mit.edu/wpmu/annualreport/?cat=6

  Spot on.
  Heat -> electricity
  beats
  heat -> mechanical motion -> electricity.

But this is heat -> light -> electricity. Unless you are claiming that the conversion from heat -> light and light -> electricity is lossless.

Actually, it's not. Not if you're using photovoltaics or anything else with a "band gap." According Einstein's Nobel-Prize-winning research, you have to "tune" the energy emitted by the material to match the band gap of the photovoltaic cell. If it's too low, nothing happens. If it's too high, the conversion is inefficient. http://en.wikipedia.org/wiki/Photoelectric_effect#Emission_m... and http://en.wikipedia.org/wiki/Band_gap

Really freaking cool, but I hear about some awesome new energy technology out of MIT every week. Any ETA on when they start using this in......anything?

My rule of thumb for stuff like this is minimum 3 years and generally 5-10 years. It has so-far seemed to be true just from about 20 years of reading about cool new technology X.

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