Material Converts Radiation Into Electricity

holy_calamity writes "Nuclear powered space probes like Pioneer have 'nuclear batteries' that (very inefficiently) convert heat from decaying isotopes into electricity. US researchers think a new material that converts radiation directly into power instead could make nuclear batteries 20 times more efficient. (Unfortunately they will likely not be user-replaceable.) The material consists of gold, carbon nanotubes, and lithium hydride."

Comments

Carbon nanotubes

[j00r0m4nc3r]

Is there anything they CAN'T do?

Re:Carbon nanotubes

[Knuckles]

Just a few things, but those are covered by Lithium, apparently.

Re:Carbon nanotubes

[ObsessiveMathsFreak]

Become affordable?

Re:Carbon nanotubes

[Farakin]

OH SNAP!!

Re:Carbon nanotubes

[zenaida_valdez]

Between carbon nanotubes and Viagra, everything's covered!

Re:Carbon nanotubes

[Anonymous Coward]

Uh, most of the life we know is based on carbon. If it wasn't that useful, *we* wouldn't be here as we are. Small pieces of it are bound to be really useful, you know, as in DNA, carbohydrates, plants, etc.

Re:Carbon nanotubes

[cbreaker]

He didn't say CARBON, he said Carbon NANOTUBES. Last I checked, life on earth isn't based on Carbon Nanotubes.

Get a life.

Re:Carbon nanotubes

[Coraon]

heh, what do you wanna bet if we discover god he will just be an elaborate sequence of carbon nanotubes.

Re:Carbon nanotubes

[Anonymous Coward]

be produced in large quantities?

Re:Carbon nanotubes

[Anonymous Coward]

Again, anonymously, I'd call for a "carbonnanotube" tag because apparently a.) they are involved in every third story and b.) they apparently have miraculous properties ranging from incredible strength/weight ratio to curing leprosy.

no obvious tags please

[Anonymous Coward]

If you tag this whatcouldpossiblygowrong then you are an unoriginal hack.

Re:no obvious tags please

[Anonymous Coward]

no obvious tags please I think you have missed the point of tagging. The name isn't what is important. What is important is that it can be used to categorize stories.

Re:no obvious tags please

[Anonymous Coward]

Darn, I already tagged 'haha'.

Re:no obvious tags please

[Anonymous Coward]

I think everybody missed the point. The "funny" tags don't categorize anything in a useful manner, since all the stories with said tags have in common is they trigger the groupthink joke gene that nerds seem to have in bulk.

Also, a free comedy lesson: laughing at it once doesn't make it funny the next thousand times. That's a lesson I doubt will ever get through around here, though.

Re:no obvious tags please

[PFI_Optix]

I like having an easy-to-remember tag for "Scientific developments that could cause serious problems if done wrong or misused."

Among these are:

creating life in a test tube
genetically modifying viruses
advanced AI in combat robots
Anything to do with nuclear materials
Building a car around a tank of compressed hydrogen

Re:no obvious tags please

[Anonymous Coward]

1. Complain about recycled humor on slashdot
2. ....
3. Profit!

Re:no obvious tags please

[Applekid]

"Scientific developments that could cause serious problems if done wrong or misused." So, in other words, every scientific development ever? That makes it less of a tag and more of a blanket IMO.

Re:no obvious tags please

[Anonymous Coward]

huh? doesn't that defeat the purpose of tagging in the first place?

Re:no obvious tags please

[Anonymous Coward]

In Soviet Russia, old jokes laugh at YOU.

Re:no obvious tags please

[Anonymous Coward]

We're all cowards

Re:no obvious tags please

[PFI_Optix]

Not at all.

Scientists: "Hey, we've got this nifty bipedal robot that can walk up stairs."

Slashdot: "What could POSSIBLY go wrong?"

Scientists: "Umm...it falls down the stairs?"

Re:no obvious tags please

[Danny Rathjens]

Also, a free comedy lesson: laughing at it once doesn't make it funny the next thousand times. That's a lesson I doubt will ever get through around here, though.

The concept is that something happens repeatedly, to the point of boredom. Then it keeps going, to the point where it actually becomes funny again. http://tvtropes.org/pmwiki/pmwiki.php/Main/OverlyLongGag
Lot's of other examples and terms that folks have used for the phenomenon here:
http://ask.metafilter.com/84851/Who-remembers-an-article-about-The-Paul-Reiser-Effect

There could be a serious benefit

[Samalie]

If this works, imagine being able to generate electricity not just from nuclear power plants themselves, but from the nuclear waste storage facility?

I would think, assuming of course this proved as pratical in pratice vs theory, that this could dramatically reduce our dependance on fossil fuels. Assuming of course you could use the "pure" radiation of the waste into electricity.

Re:There could be a serious benefit

[asuffield]

If this works, imagine being able to generate electricity not just from nuclear power plants themselves, but from the nuclear waste storage facility?

To heck with that, and with batteries - imagine being able to generate electricity from nuclear power plants themselves, rather than using them to heat water, shove it through an inefficient turbine, and then let most of the energy evaporate off in a cooling tower. The steam turbine system is horrendously inefficient. Cutting all of that out of the loop would make nuclear power so hilariously efficient that nobody would care about the waste storage (we wouldn't need much of it anyway). It would also be far safer: a lot of the stuff in a current nuclear plant goes into managing the water moving through the reactor, which is all expensive, fragile equipment that gets mildly contaminated. Replacing all that junk with some electrical cabling would be a major breakthrough.

Re:There could be a serious benefit

[DCGaymer]

One word.....Chernobyl Could it be used on something like that I wonder?

Re:There could be a serious benefit

[Anonymous Coward]

Not only would U and Pl be sources of energy, but what we now consider to be nuclear waste could be used to generate power.

Re:There could be a serious benefit

[DigitalSorceress]

That's the first thing I thought of when I read the article... You get double-use out of the nuclear materials:

phase 1: generate power with standard fusion
phase 2: take the waste to a secondary waste-to-energy facility
phase 3: PROFIT!

After all, we're currently just burying (or would like to) our waste since it will be "hot" (in a radioactivity sense if not a thermal sense) for a long, long time. Why not get that extra bang for the buck? We've got the waste anyway, so why not get a bit of benefit from it.

In theory, I would think that the action of extracting some of the energy from the radiation would consume some of it... simple thermodynamics: the more efficient the energy extraction, the less waste radiation bouncing around inside the containment facility.

Hmm, maybe they could even line use this stuff directly in the primary plant as well?

I'm only speculating, but my guess is that this would have been on the minds of the inventors.

Re:There could be a serious benefit

[BlueParrot]

If this works, imagine being able to generate electricity not just from nuclear power plants themselves, but from the nuclear waste storage facility?

Let's consider that for a moment. Nuclear fission releases about 200 MeV per nucleus, while radioactive decay releases about 5MeV per nucleus( assuming alpha emission ). Thus even assuming 100% efficiency for this tech, and only 30% efficiency for existing reactors, fission gives you more than 13 times more energy than the radioactive decay, and this is assuming that you have enough time to wait for all nuclei to decay. In practice, because most of the alpha-emitters have half lives measured in thousands of years, the total amount of energy that could be generated by this tech per year would be thousands of times smaller than that from fission, so you're better of just building a second reactor.

Re:There could be a serious benefit

[Anonymous Coward]

Excellent point.

Re:There could be a serious benefit

[MrMacman2u]

Another point to ponder is imagine if they could use this material in a way that there TECHNICALLY wouldn't be much waste from current planet designs until they master this technology enough to generate electricity solely from it and traditional planets are being phased out.

While nuclear waste from current reactors is no longer good for creating the massive quantities of heat needed to run a steam turbine, the radiation levels stay extremely high for decades and the "waste" could be placed in a secondary, lower power, facility and used to create electrical power LONG after it's usefulness as traditional nuclear "fuel" has been expended.

This could help buy time for traditional plants to be pushed out smoothly because they would just be producing a lower grade "fuel" for the new plants. The possibilities and usefulness of this material is enormous. I can't wait to see how/when they decide to put this into production.

This is one product that could truly change the world for the better if it doesn't end up being vaporware!

Re:There could be a serious benefit

[drakaan]

Thus even assuming 100% efficiency for this tech, and only 30% efficiency for existing reactors, fission gives you more than 13 times more energy than the radioactive decay, and this is assuming that you have enough time to wait for all nuclei to decay. In practice, because most of the alpha-emitters have half lives measured in thousands of years, the total amount of energy that could be generated by this tech per year would be thousands of times smaller than that from fission, so you're better of just building a second reactor.

So, fission would give you thousands of times more energy than radioactive decay, but can't keep doing it with the same material for thousands of years (basically the anti-point to your point about how long it takes to get the energy from decay).

Time aside, comparison becomes a matter of how much space each type of power plant takes up for a given amount of continuous power generation.

Let's say that you need 1000 times as much decaying uranium to generate the same amount of power as you get with fission. You need more space for the uranium, but no space for a cooling tower, pumps, turbines, backup generators, meltdown containment, etc, etc. How much of the space used by a conventional nuclear power plant is occupied by the actual fuel? Who cares to hazard a guess that we're approaching parity, in terms of reactor size for the two approaches?

Beyond that, retrofitting existing reactors with auxiliary power generation stations that use what is now considered "spent" fuel would eventually supply as much power as the current reactors do, and they'd keep doing it for thousands of years with the same fuel (you'd have to do maintenance, of course).

In the short term, building new fission reactors makes good sense. They're fairly safe, and the fuel they use now becomes food for the technology we're talking about after it's not useful in existing reactors.

What *I* want to know about is how effective this material is as a radiation shield. Something that can both protect you from radiation and generate electricity seems awfully handy.

Re:There could be a serious benefit

[Duhavid]

One thing to factor into your thinking is that there is probably a lot more
waste material sitting around than is active in cores of reactors. Also, I
would think that that waste material would be producing at the lower figure,
but for a much longer period of time.

Re:There could be a serious benefit

[BlueParrot]

Beyond that, retrofitting existing reactors with auxiliary power generation stations that use what is now considered "spent" fuel would eventually supply as much power as the current reactors do, and they'd keep doing it for thousands of years with the same fuel (you'd have to do maintenance, of course).

Let me put things into perspective for you. Sweden's current fleet of nuclear reactors provide 25% of it's energy demand. If operated for about 60 years they will produce enough spent fuel to fit in a 10m cube. If this waste is recycled in fast reactors, the fissioning of the uranium still in it could power Sweden's present energy consumption for more than a thousand years.

Essentially, neither space nor resource availability is an issue for nuclear power stations. The vast share of the cost lies in their construction so the only way this could possibly outdo present plants would be if they could achieve better than about 40% efficiency with less material investments. This is when you get issues. To circumvent the limits set by the second law of thermodynamics you must capture the energy before it is transformed into heat, which effectively means you need to embed the fuel into the transforming material, and this in essence means you need as much of this material as the fuel you are extracting energy from. Thus not only do you need more than thousands of times as much material as for a fission plant, you also need the corresponding quantity of material capable of converting the radiation into electricity. Simply sticking all the radioactive material in the center and have the conversion outside of it won't work since much of the radiation will be lost as heat if it passes as much as a millimeter of other material ( in contrast to x-rays and neutrons, the most energetic part of the radioactive decay comes from alpha and beta decays, and alpha/beta radiation is blocked by even thin foils of metal.).

Simply put, by the time we have the technology to make this even a plausible replacement of nuclear power stations, we will likely have technology that makes the construction of a nuclear power station substantially cheaper than it is today, thus greatly offsetting the benefit.

Re:There could be a serious benefit

[BlueParrot]

Also, I
would think that that waste material would be producing at the lower figure,
but for a much longer period of time.

Doesn't matter, you get 200 MeV per fission ,and about 5MeV per alpha decay, if those events happen instantaneously or over the course of millions of years make little difference, fissioning a nucleus simply emits more energy than radioactive decay. The amount of energy that can be extracted from a given number of nuclei when they fission is simply greater than the energy that can be extracted when the same number of nuclei decay through alpha emission.

Also, the quantity of spent nuclear fuel is much lower than most people seem to think. A nuclear reactor refuels only about once a year or every few years. So running it for 60 years will produce at worst 60 cores worth of material, 95% of which is still uranium. The fission products only make up some 4% of the waste. If you take it even further and assume you use fast breeder reactors, then you could essentially run a reactor on the initial uranium load for several decades, and the fission products produced would be in comparable quantity to the uranium you suplied.

Also, note that my figures were for alpha emitters, the most energetic of radioactive decay. In reality the fission products are either beta-emitters or nonradioactive (and virtually all the alpha emitters are heavy nuclei that can be used as fission fuel instead ), so the numbers are easily an order of magnitude worse still. This also ignores the fact that the energy could be recovered in other ways. You could as an example just recover the energy from the decay as heat, which would essentially just require that you put the waste in a seal container that you cool with the water you want to heat.

Simply put, the main advantage of this form of energy generation is that you can circumvent the carnot limit since you never convert the energy to heat. However, since modern developments of heat engines have pushed the achievable temperatures up to the point where 40%-50% efficiency is feasible, you could at best double the efficiency and I really doubt it would be worth the effort. Increasing the temperatures at which our heat engines can operate ( thus improving their efficiency further ) seems like a more realistic solution.

Re:There could be a serious benefit

[Duhavid]

I don't see it as either / or.

Yes, use fission, and reprocess the fuel to the extent possible, and work to
increase reactor efficiency, but once that fuel is out of the reactor, why not
*add* this new technique and continue to generate lower levels of electricity
from that. Assuming it works, of course.

During that same 60 year cycle, you will have, each year, one more core set
to do something with. You are not going to get that 200 MeV from it, it is not
in a reactor, why not go ahead and get that ( 5 * number of cores * n years ) MeV
from that, rather than just storing it.

Re:There could be a serious benefit

[Carbon016]

Most of Chernobyl is no longer very radioactive. A new "coffin" lined with this would be an excellent replacement for the aged cracking one surrounding the destroyed reactor, though.

Re:There could be a serious benefit

[Thelasko]

The steam turbine system is horrendously inefficient.

Compared to what? I have news for you. Steam Turbines are one of the most efficient engines we have. That's why we use them!

The second law of thermodynamics says that no engine can be 100% efficient. The reason is, a 100% efficient engine would require an infinitely hot source of energy and infinitely cold surroundings, assuming there is no friction. Carnot, says that the best we can hope for is more like 60-70% efficiency, and Rankine, suggests that a more realistic number is somewhere between 40-50%. That "inefficient turbine" you speak of is 40% efficient in reality. That's pretty good considering the best we can hope for is 60-70%.

I am not a nuclear physicist, but the laws of thermodynamics still apply. We can still only hope for 60-70% efficiency, but for various reasons we still won't be able to archive this. Now, instead of letting "most of the energy evaporate off the cooling tower" we will be radiating it to the surroundings instead. Fine for spacecraft, not fine here on Earth. Even though this technology sidesteps the creation of thermal energy it still must obey the laws of thermodynamics.

Re:There could be a serious benefit

[Thelasko]

What *I* want to know about is how effective this material is as a radiation shield. Something that can both protect you from radiation and generate electricity seems awfully handy.

I'm guessing it's only slightly more effective as a radiation shield as it is at producing electricity. (i.e. radiation not turned into electricity passes through the material.) But I could be wrong.

Re:There could be a serious benefit

[hedwards]

If this works, imagine being able to generate electricity not just from nuclear power plants themselves, but from the nuclear waste storage facility? That's inspired. Using them to coat the interior of the core is obvious, but coating the interior of storage facilities with the stuff is just inspired.

Combine that with current recycling and re-refining techniques and that's got to be a significant step forwards for nuclear energy.

Re:There could be a serious benefit

[BlueParrot]

Because the fission products decay by beta emission, which generates about 1/2000 times the energy of fission, which means that if you do this at the back end will add a pathetic 0.05% to your energy output, and you could get the same effect by just using the heat from the radioactive decay for district heating or some other much easier to implement heat-conservation scheme.

Re:There could be a serious benefit

[evilbessie]

If you can name 5 technologies at power generation than a steam turbine, and also work on the same scale (Gigawatts) I could accept your horrendously inefficient claim. But from what I can recall from somewhere in my brain, modern steam turbines are 50-60% efficient while most other generators are in the 30-50% range. I could of course be wrong.

Re:There could be a serious benefit

[asuffield]

Compared to what?

Compared to the amount of energy wasted. Most of it is lost in the cooling towers that are needed to keep the cycle closed, the rest is lost in transfer from the core.

Steam Turbines are one of the most efficient engines we have. That's why we use them!

Yes. And guess what? The most efficient system we have is not very efficient at all. Also note that the main problem is not the turbine itself, but the system as a whole used to transfer energy from the nuclear core to the grid output.

Carnot, says that the best we can hope for is more like 60-70% efficiency, and Rankine, suggests that a more realistic number is somewhere between 40-50%.

Which is precisely why a system based on a new material like this, which does not involve the Carnot (or Rankine) cycle at all, would be hugely more efficient. The whole point is that heat transfer systems are not a good way to extract energy from a nuclear power plant, because of those intrinsic inefficiencies.

Re:There could be a serious benefit

[Thelasko]

The materials they are testing would extract up to 20 times more power from radioactive decay than thermoelectric materials, they calculate.

Wikipedia says, "most RTGs have efficiencies between 3-7%" Since 20x7%=140% I don't think that's the value they are using. I think they are using 3% efficiency since that makes their discovery look good. That gives this new material a theoretical efficiency of 60%. This is analogous to an engine's Carnot efficiency and therefore I expect it to be far less in reality.

Let's assume the material is as efficient in reality as a steam turbine (40%). Then yes, it will be more efficient than current nuclear power plants. However, instead of the power plant releasing heat energy into it's surroundings, it's releasing radiation.

No problem, we will just surround the thing with lead so the radiation doesn't hurt anybody. That won't work, because without a place for the radiation to go the system doesn't work. The radiation will just bounce off the lead and cancel out in a closed environment (once again I'm not a nuclear physicist). You still need to get rid of it, convert it to heat, bury it in a mountain, or radiate it into space. How much does that effect the systems efficiency? I'm betting on this material having a practical efficiency of around 15%. It will be better than an RTG but not good enough to replace current power plants. I make this statement mostly because it sounds similar to photovoltaics.

Re:There could be a serious benefit

[Adriax]

What the flying fuck are you talking about? Lead absorbs radiation, not reflect it. What good would lead shielding be if it just reflected it back?
This stuff works kinda like a solar cell, taking the decay radiation instead of light and using it to knock electrons down a one way path.

I'm curious as to how this would work in orbit with cosmic radiation. Would it be worth it to slap this stuff on the underside of normal solar cells on satellites?

Re:There could be a serious benefit

[asuffield]

The radiation will just bounce off the lead and cancel out in a closed environment (once again I'm not a nuclear physicist).

We can tell. That's nonsense. Lead does not reflect radiation - most notably, it absorbs alpha, beta, and gamma radiation. Although in practice we use concrete, it's cheaper and more effective.

without a place for the radiation to go the system doesn't work

The radiation goes into the converter material and comes out of the system as electricity. That's the whole point.

Not really having much confidence in your guesses at this point.

Re:There could be a serious benefit

[felisconcolori]

I'm not a mechanical engineer, but... ... What would thermodynamics do with the efficiency of conversion of a system that does not use dynamic thermal changes to produce energy? Granted, it may have effects, but this system does not appear to be an "engine" in any traditional sense; closer to a photo voltaic cell than a mechanical system. Which, after all, is all that a steam turbine is.

Re:There could be a serious benefit

[reiisi]

Isn't imbedding the fuel in carbon one of the things already done?

What I'm wondering about is where the slowed-down alpha particles go. Do they re-capture the slowed-down beta particles (the ones that aren't anti-particles) and float up into the atmosphere?

But if the beta particles are being diverted into electrical circuits, are we going to have ESD problems?

Is having excess helium going to do funny things to the ozone layer?

Guess I should go off and look this up somewhere. Maybe the friendly article.

Re:There could be a serious benefit

[Rei]

To heck with that, and with batteries - imagine being able to generate electricity from nuclear power plants themselves, rather than using them to heat water

To heck with that, too. You did notice that the tech involves lots of gold, right? It's bremsstrahlung radiation from the collision with gold that causes the shower of electrons that is captured.

Now, perhaps a *future* technology might use some other metal as the target. But this one would clearly be way too expensive to enclose a reactor or waste storage facility with.

Re:There could be a serious benefit

[Thelasko]

Lead absorbs radiation, not reflect it.

I couldn't find any information about it absorbing or reflecting at the time of writing. That's why I noted that I'm not a nuclear physicist.

Re:There could be a serious benefit

[Thelasko]

I'll believe it when I see a reference. If the lead absorbs the radiation where does the energy go?

On a hot sunny day, do you wear a black shirt or a white one? Why?

Re:There could be a serious benefit

[SoapDish]

The Carnot cycle describes an ideal *heat* engine. As such, it only the most efficient way to convert heat to mechanical power.

This is a different kind of engine. So, it is not held back by the same limits as the carnot cycle, but by other limits.

Re:There could be a serious benefit

[Anonymous Coward]

Me too!

Re:There could be a serious benefit

[WindBourne]

How does 78% carnot sound?

Re:There could be a serious benefit

[Zencyde]

Or, perhaps airplanes? Seriously, imagine being able to transport goods and people for next to nothing. Shipping costs would go down. Flight costs would go down. The world of e-commerce would become very popular. Trains would be capable of traveling faster and for a cheaper cost. There's so much that could be done with this. Although, nuclear submarines might be a different story. What of the breeder reactor?

Re:There could be a serious benefit

[amorsen]

What *I* want to know about is how effective this material is as a radiation shield. Something that can both protect you from radiation and generate electricity seems awfully handy. The material consists of a layer of gold followed by some light stuff to catch the electrons. I bet the layer of gold would do >50% of the radiation shielding, so that should get you in the right ballpark. Gold is very good radiation shield, I can certainly recommend that we use that around our reactors instead of the concrete that is popular today.

Re:There could be a serious benefit

[Anonymous Coward]

I can certainly recommend that we use that around our reactors instead of the concrete that is popular today.

Advantages of concrete...

It's inexpensive.

Easy to work with on macro scales. When you need, say, 24" of shielding using concrete, you don't have to be very precise. (I don't know what the usual width of shielding is, but 24" feels reasonable.) An eighth inch one way or the other doesn't change much about how well it works or how much it costs.

It's also easy to maintain and repair. And easy to detect that it needs repair, because damage is generally visible to the naked eye.

A thin layer of gold is much more difficult to get right. More difficult to verify correctness, and probably harder to repair.

Re:There could be a serious benefit

[amorsen]

A thin layer of gold is much more difficult to get right. More difficult to verify correctness, and probably harder to repair. It wouldn't be thin, if it was to replace the concrete. Tens of centimeters at least. I don't think verifying correctness would be a big problem, and gold is a very easy material to work with. It could be a problem that gold is such a good conductor of heat, but otherwise I don't foresee major difficulties.

Re:There could be a serious benefit

[asuffield]

Perhaps you missed the article. We're talking about a new technology that works on a different principle, which happens to escape the fundamental efficiency limits of a heat-transfer cycle, and hence could potentially be developed into a far more efficient nuclear power generation method.

And the actual thermal efficiency of a steam-cycle nuclear power plant is in the 5-30% range (with most of the ancient, 1960s reactors that you find in the US and western Europe coming in at the 5% end - new reactor designs give a more respectable 30%, but when did you last hear of somebody building a new reactor?).

Re:I'm sorry

[cosinezero]

This is insightful?? What about the issue pointed out in the article?!? Satellites? Hey, let's recall Voyager just to replace it's batteries, then send it out for another 30 years.

Why is it...

[narrowhouse]

that all these neat technologies depend on exotic materials? Just once I would like some really cool technology to be dependent on something cheaper and easy to obtain, while being ten times more efficient that the gold/lithium irradiated crystals it replaces.

Today's news: hobo sweat and nail clippings mixed with Diet Coke and mentos == cold fusion.

Re:Why is it...

[Anonymous Coward]

You think hobo sweat and nail clippings are easy to obtain? Trust me, chasing them and holding them down while you get the supplies is a lot more work than you expect. Unless we set up some sort of hobo farm, I don't see your plan being feasible.

Re:Why is it...

[pla]

Why is it ... that all these neat technologies depend on exotic materials?

Because most of our existing technology comes from adapting what we've observed occurring more-or-less naturally in the world around us, and we've already plucked all the low-hanging fruit.

If you want to understand how to extract energy from hydrogen sulfide, you can study deep sea vent bacteria. If you want to understand how to directly convert radiation to electricity... Well, we don't know of anything that already does that, so if such a phenomenon exists (which seems reasonable), it makes sense to start with some of the most exotic substances we know of.

Re:Why is it...

[MarkGriz]

Clearly you've never heard of "youtube"

In fact, there's an entire army of people who've figured out you can power an automobile entirely from plain water.
They have videos and everything. It's totally amazing.

What's really surprising is that the auto industry hasn't incorporated this amazing discovery into their new vehicles.

Re:Why is it...

[Punko]

if you want to understand how to directly convert radiation to electricity... Well, we don't know of anything that already does that, so if such a phenomenon exists (which seems reasonable),

Photovoltaic cells convert radiation in to electricity. DIRECTLY. Of course, its only EM radiation that falls within a specific energy profile, and doesn't include alpha, or beta particles, but at least the certain range of gamma radiation is covered.

Re:Why is it...

[Jon Eiche]

Hear, hear! Years ago, Steve Martin proposed the ideal material to collect solar heat: Car seats.

Re:Why is it...

[daemonhunter]

And me without my mod points....

Re:Why is it...

[geekoid]

haha, seriously You tube videos? Yes, that all the evidence we could need.

The ater powered aoutomobile is a fraud. Or I should say, all studies of them have only found some fraudster at the heart.

You're right, if they could make practical cars that are fueld by water the Auto industry would be all over it. It would litterally save the American autoindustry, as well as meen billion dollar bonuses. If not the US car companies, then any one of the other car companies. Hell If you could gat a car, prove it runs on cheap water there are a number of VC that would gladly help you start your own company.

Sadly, they require PROOF, of which there is none.
Sad really.

I really hope this is a joke that went over my head and not a seriously lack of science and deductive reasoning on your part.

Re:Why is it...

[brunes69]

But then hobos would be in such high demand you would never be able to find any when you wanted to watch a good fight.

Re:Why is it...

[pla]

Photovoltaic cells convert radiation in to electricity. DIRECTLY.

Fair catch, I should have stated my point more specifically... But you know what I meant. :)

Re:Why is it...

[wattrlz]

Sure you would. What do you think we'd do with them after they'd been harvested? Heck, you could have them fight over a grate and some sluices and collect the sweat that way...

Re:Why is it...

[Punko]

Yes, I knew what you meant, but hey, this is Slashdot!

Re:Why is it...

[Anonymous Coward]

Sunlight is radiation...
Anything around here convert sunlight to something useful?
Plants? Solar panels? Your skin? Yoda?

Re:Why is it...

[damburger]

Simply because we have been juggling petrochemicals around for decades and have found most of the useful things they can do already.

Nanotechnology is developing as petrochemicals did decades ago. When substances are reduced to nanoscale particles, their properties change so drastically they might as well be new materials. This means that physicists are suddenly discovering thousands of new substances at once and want to see what they can do, just as chemists did with petrochemicals.

Re:Why is it...

[Anonymous Coward]

"Unless we set up some sort of hobo farm"

I think you can gather from the sub-prime home loan crisis that our governments are already well advanced in a scheme to mass-produce the homeless.

Re:Why is it...

[Anonymous Coward]

Bah. Everyone knows you can't farm hobos. They're migratory by their very nature! Hobo ranching is where it's at.

Re:Why is it...

[Bob-taro]

...it makes sense to start with some of the most exotic substances we know of.

I was with you right up to the end. I'd like to think the substances in question were chosen for the experiment because of their physical characteristics, and not JUST because they are exotic.

Re:Why is it...

[QuantumRiff]

Wool.

Shave a sheep, cover yourself in the shavings. You'll stay warm, even if you get wet. How cool is that!?

Re:Why is it...

[Goobermunch]

We already have a hobo farm. It's called New Jersey.

--AC

Re:Why is it...

[stonecypher]

Today's news: hobo sweat and nail clippings mixed with Diet Coke and mentos == cold fusion.

Whoa, hobo nail clippings are made of Mentos?

Re:Why is it...

[stonecypher]

Nothing worse than noticing the fail in your joke right after you hit submit. Nothing to see here. Move along.

Re:Why is it...

[Forrest Kyle]

Unless we set up some sort of hobo farm

Have you ever been to Seattle?

Re:Why is it...

[MagusSlurpy]

[quote]Unless we set up some sort of hobo farm, I don't see your plan being feasible. [/quote] Since when was San Francisco unfeasible?

Re:Why is it...

[MagusSlurpy]

Whoops. Too much phpBB posting. I fail at /.

Re:Why is it...

[Mac Degger]

And that's why it's a good idea to research the bacteria/moulds etc which live in and near Chernobyl. Life 'finds' a way, and thanks to the random changes/evolution of the lifeforms there, some very interesting and potential mutations can have popped up there.

We'll have to go look, though.

Re:Why is it...

[Fex303]

Unless we set up some sort of hobo farm, I don't see your plan being feasible.

We have one of those. It's called New York.

Re:Why is it...

[Fex303]

Oh damn. Didn't read the other replies. Guess I'm not as original as I thought.

Re:Why is it...

[MarkGriz]

I guess the mods didnt get the joke either. oh well.

Re:I'm sorry

[Osurak]

If you think of the sun as a power source, it's not exactly user-replaceable either, but I'll be damned if its battery life isn't unbelievable.

Re:I'm sorry

[antikaos]

Robots

Re:I'm sorry

[mo^]

Devices based on the material could be small enough to power anything from interplanetary probes to aircraft and land vehicles, he adds.

I think once we get to the level of space probes, "User Serviceable" is not particularly essential. Christ, I wont even change my car battery (due to laziness as much as anything).

Were you envisaging using these in your remote or something?

Another application for this!

[jameskojiro]

Would be to use int he reactor of a Nuclear rocket to generate electricty during the coasting phase between planets. If you go further than Mars Solar panels just ain't gonna cut it.

Re:I'm sorry

[Andy Dodd]

Guess it depends on your definition.

If you mean being able to replace the fuel but not the conversion hardware and shielding - almost surely not.

If you mean being able to replace the whole fuel + conversion stuff + shielding assembly - possibly. This whole assembly would be very expensive, but could potentially be sent back to a facility for recycling. (i.e. replacing the fuel inside the assembly)

Keep in mind that depending on the type of fuel used, a low power density (large and heavy for its power output) device could potentially have a life of 10,000+ years...

Re:I'm sorry

[AKAImBatman]

So what you're saying is, 20+ years of power-source* life isn't good enough for your iPhone? Quick! Yell at Steve Jobs! How DARE he make phones that need a trained professional to replace the power unit after 20 years! I mean, so what if the last GSM tower will be removed by the time the battery peters out? So what if the screen shatters, the touch area goes dead, and the sound becomes fuzzy? It's the principle of the thing I tell you!

Um. Yeah. :-/

* I say "power-source" because nuclear batteries are not actually batteries. They are long-lasting power generators that cannot be turned off.

LOL

[Anonymous Coward]

Hilarious!

Radiation is the best.

Re:I'm sorry

[Darkfred]

Idiot,
Some isotopes proposed for this use have lifetimes longer than yours, making the battery and device containing it effectively permanent.
In fact half the problem is finding ones that have a half-life short enough to give good power for say 10 years yet don't decompose into poisons or release gamma rays. Which isn't really a problem on interstellar space probes, but makes it difficult to develop consumer devices.

Re:I'm sorry

[Anonymous Coward]

I don't think user-replacement is a priority for deep-space probes

Re:I'm sorry

[Anonymous Coward]

If the battery gets 1000 years of life, I really don't care if my great great great great great great great grandchildren have to pay somebody else to replace it. I'll put $10.00 in an investment account, and it'll be plenty of money by the time they need it.

Also, grow up.

Re:I'm sorry

[Arcturax]

That was tried once, but the inventor was sucked into cartoon and died a horrible and ironic, yet still amusing death.

Re:I'm sorry

[Anonymous Coward]

And why the hell wouldn't this be user-replaceable? No where in the article does it mention that it wouldn't be. I would picture this just like an alkaline battery. Sure, you can't replace the chemicals inside one of those that make it work, so you throw out (or recycle) the entire assembly: case, electrodes, chemicals and all. These could be made the same way. To the end user it's a non-conductive block with two electrodes, one for plus and one for minus. When its electricity generating days are over, pop the whole thing out and put in a new one. End of story. How many of us refresh the acid in our car batteries or tamper with the non-rechargeable lithium cells? Jeez.
-Will

is it green ?

[Atreide]

article mentions use in fission reactor.

when producing electricity,
will it consume (remove waste) radiation
or will it only use radiation ?

Analogy to Photoelectric effect

[Mad Hughagi]

Same basic idea.

Waste...?

[Half-pint HAL]

Cutting all of that out of the loop would make nuclear power so hilariously efficient that nobody would care about the waste storage (we wouldn't need much of it anyway).

Actually, you've missed an important point about nuclear waste. Nuclear waste is dangerous because it's still radioactive. However, it's useless because it's no longer fissile and hence can't be used in a nuclear power plant.

This technology should be just as efficient with nuclear waste as with fissile materials. However, the problem with this technology is time. Fission releases a lot of energy very quickly, but most most common radioisotopes have very long half-lifes, releasing their radiation over thousands of years. (Anything with a short half-life will have "died" millenia ago.) The applications for this will be relatively low-power, long-term projects.

HAL.

Re:Waste...?

[BlueParrot]

However, it's useless because it's no longer fissile and hence can't be used in a nuclear power plant.

Not true, spent fuel is discharged not because it is depleted of fissile material but because other elements generated in it absorb neutrons. If you remove those elements chemically the fuel can be re-used, and with some fast reactor designs you can even ensure that they produce the same amount of fissile material as they consume ( by converting U-238 into plutonium ). The end result is about 100 times better uranium utilization and nuclear waste which decays to uranium levels of radioactivity within 300 years or so.

Re:Waste...?

[SatanicPuppy]

BlueParrot is 100% correct; if we reprocessed our nuclear waste it would virtually eliminate our waste storage problems. The final product would be much less radioactive, and degrade much more quickly.

The only reason it's not done is that re-enrichment produces large amounts of bomb-grade material, which could theoretically be stolen and used to make a nuke, as opposed to our normal waste which is pretty much useless.

This is getting to be a poorer and poorer excuse as time goes on, as more and more unstable countries learn to do the bomb thing for themselves. All we're really doing is saddling ourselves with a nasty radioactive waste problem.

Re:Waste...?

[Anonymous Coward]

Nuclear Electricity is truly remarkable when you realize that only 1 or 2 percent of the fuel is actually being consumed and it is still competitive with coal.

Re:Waste...?

[hesaigo999ca]

Built any nuclear bombs lately have we???

Re:Waste...?

[Thelasko]

We also signed some treaties that limit the amount of "bomb-grade" material we can produce.

Re:Waste...?

[BlueParrot]

No, but if I were to try I would use low-burnup thermal reactors on PUREX reprocessing rather than ultra high burnup fast breeders with full actinide recovery heavily spiked with transuranics that have high rates of spontaneous fission. Alternatively I'd go for highly enriched uranium.

Seriously thou, modifying the reprocessing cycle for a fast breeder and then use the very low grade plutonium to produce a nuclear weapon would be so unpractical that it would probably be easier to just start a uranium based weapons program from scratch. Simply separating the plutonium from traces of very troublesome elements with high spontaneous fission rates ( think californium, einsteinium ... ) would require a reprocessing plant unlike anything ever constructed or proposed. Building a nuclear device out of the recovered plutonium ( which would have a much less suitable isotopic composition than traditional reactors ) would require groundbreaking research into nuclear weapon design, and probably a number of tests.

At the end of the day the effort involved would likely surpass that needed to build a more traditional graphite moderated reactor and extract the plutonium from that. I.e, even if somebody was to give you the reprocessing plant for a fast breeder with actinide recycling, as well as the spent fuel, you would probably have an easier time trying to do it the old fashion way. In addition it is hardly as if a rogue nation with the necessary economics would not be capable of building a nuclear weapon anyway. The technology is more than 6 decades old.

Re:Waste...?

[Anonymous Coward]

This is getting to be a poorer and poorer excuse as time goes on, as more and more unstable countries learn to do the bomb thing for themselves.
That is the funny thing. NONE of these unstable countries figured it out for themselves. America did. Supposedly USSR, and China "borrowed" from America. I am not certain, but I believe that America helped Britain and France with their programs. Ditto for Israel. I believe that India did figure it out on their own. But the real problem is that top republicans (pearle, cheney, etc) SOLD American nuclear bomb making information to Turkey AND Pakistan. Pakistan did not figure it out. Since then, Pakistan did spread, and Turkey has sold it around as well.
Supposedly, Bush is planning to push Turkey as being one of our Nuclar partners whereby they will process nuclear material. Yet, they do not have the real knowledge for it. Yet.

It will be interesting if SIbel Edmunds is ever ungagged. I wonder how many other top republicans will go to prison. I am guessing zero. I think that the dems will not undo the gag because some of them will go down.

Re:Waste...?

[Bert64]

Germany were fairly close to working it out for themselves too...
The USSR may have recovered some of the german research after the war, and america certainly took some of their scientists.

Re:Waste...?

[Random Q. Hacker]

So at some point in the future can we get all those drums of radioactive waste, and reprocess/re-enrich them into fuel? Or do they do something to the waste before storing it?

MOD PARENT DOWN

[Anonymous Coward]

Score:-1, Troll

I need a rest

[clickclickdrone]

My first thought on seeing the headline was if a nuke went off, I'd have the choice of getting fried by radiation or electrocuted by the suit.

Shielding?

[Bombula]

Would this material make good radiation shileding? Seems like manned spaceflight could make use of a material that did double-duty as radiation shields and solar panels.

Re:Shielding?

[Falladir]

I think the trouble with radiation in space is that the energies are so high. This stuff isn't a more effective shield than lead or water, I'd expect. The news is its ability to generate electricity in the process.

Re:I'm sorry

[Anonymous Coward]

let's recall Voyager just to replace it's batteries, then send it out for another 30 years. Not to worry. If we're willing to wait a little longer, I'm sure a group of super-powerful aliens will bring it right back to us.

I for one...

[Anonymous Coward]

welcome our recycled tag overlords.

Re:I'm sorry

[TooMuchToDo]

Think about building several of these self-contained units, and burying them in the ground in third world countries. While not a perfect solution, it's basically free power to help countries become developed, while using a carbon-free energy source.

Re:I'm sorry

[TooMuchToDo]

Technically, all batteries "generate" power through a chemical reaction, but I don't want to split "potential" hairs with you ;)

Can it convert...

[Anonymous Coward]

Background radiation?

Re:I'm sorry

[AKAImBatman]

Technically, all batteries "generate" power through a chemical reaction

'Tis true, but generally when we refer to batteries, we're referring to something you "store" energy in by moving it from a lower chemical state to a higher chemical state. You can then retrieve that energy at a later time, minus the entropic losses.

I don't want to split "potential" hairs with you ;)

Dude, you're killing me here. Really. I'm on the floor, dying from the uber-groan I just let out. Help! Auuuuugggggghhhhhhhhh---

(Who writes auuuggghhhh when they're dying? :P)

Probably much less efficent than steam

[erice]

The article didn't discuss any absolute efficiency numbers. It only said the new tech was much more efficient than thermoelectric generators, whose efficiency is abysmal. There is no mention of having efficiency better or even comparable to a steam turbine.

Steam turbines are mechanically complicated and smell of old tech but they are actually rather efficient. Large steam turbines have thermodynamic efficiency in the 90% range. I rather doubt this new nuclear photocell is anywhere close.

Re:Probably much less efficent than steam

[asuffield]

Large steam turbines have thermodynamic efficiency in the 90% range.

That's the loss in the turbine itself - the number most favourable to the turbine manufacturer's marketing department. The main loss in a steam turbine system is in the required cooling/condensing apparatus that must accompany the turbine to close the cycle.

Actual thermal efficiency for nuclear plants tends to be in the 5-30% range. The 40-year-old designs that comprise most plants in the US and western Europe are appalling; current designs manage about 30% at their optimal power level, but nobody's building new plants these days so there aren't many of them around.

Re:Probably much less efficent than steam

[Grayswan]

Got these from google with "plant vogtle new reactors". Not sure where things are RIGHT now, but the wheels ARE turning.

Georgia's twin-unit Vogtle plant has space for four reactors.

In August 2006, Southern Company filed an application with the U.S. Nuclear Regulatory Commission for an Early Site Permit for new units at Plant Vogtle, located near Waynesboro, Georgia. The permit will allow the Nuclear Regulatory Commission to review and pre-approve the plant site for future construction of new nuclear units and allow Southern Company to conduct design, construction, and other site-specific evaluations before we make the decision to build. We also would need approval from the Georgia Public Service Commission before making a final decision to build the new units.

from this month:

Georgia Power wants to build two additional 1,200-megawatt reactors at its Vogtle plant near Waynesboro. The utility is preparing to file an application with the federal Nuclear Regulatory Commission, which looks at safety and siting. However, the company also needs approval from the state Public Service Commission on how much the units would cost.

Re:Probably much less efficent than steam

[KillerBob]

Steam turbines are mechanically complicated and smell of old tech but they are actually rather efficient. Large steam turbines have thermodynamic efficiency in the 90% range. I rather doubt this new nuclear photocell is anywhere close.

Can you think of a reason this kind of technology can't be used in conjunction with a steam turbine? Modern nuclear reactors almost all work on basis of using radiation to heat up water, turning it into steam which then turns a turbine. But the water doesn't trap all of the radiation. Why not install something like this around the water tank to trap any radiation that doesn't get used to heat up water? Even if it's only able to trap 5% of the energy that's bombarding it, it's still better than the 0% that gets converted back to electricity by traditional shielding.

MOD PARENT UP

[Tangent128]

+1 Funny (Don't you know an iPhone joke when you see it?)

Re:I'm sorry

[Brian Gordon]

_IT IS A JOKE_

Are hydrogen and silicon common enough for you?

[Bovius]

You did see the article on room-temperature superconductors last week, right? Hydrogen and silicon are among the most common elements on Earth. That may not meet your standards for neatness, though, since it requires high pressures.

Hirsch-Meeks fusor?

[OglinTatas]

Might this material make the Hirsch-Meeks fusor energy positive?
Or are the unnamed "radioactive particles that slam into the gold" not neutrons?
Is the energy recovery from this material, even 20 times better than thermoelectric materials, not nearly good enough to extract enough energy from the fusor?

Radiation versus radioactive particles

[Anonymous Coward]

It will not do anything to the radioactive material. Merely that as it decays, or fissions, these fancy nano-tube thingies will absorb the decay particles (since it mentions particles explicitly, I'm assuming they mean either alpha or beta particles, possibly free neutrons, but not gamma rays). In short, you still have to wait for the material to decay.

Assuming that as decay happens, a nano-tube thingy happens to successfully interact with a particle (ie, it doesn't miss), then whether or not radiation is released depends on how efficiently it captures energy from the particle. There is no mention of that in the article.

Overall efficiency is not mentioned either. In a solid mass of fuel like in a Pu-238 spacecraft RTG, most of the energy in the form of alpha particles goes towards heating the fuel mass, because the particle is overwhelmingly likely to run into another Pu-238 atom before exiting the lump of fuel. So in practice, to achieve a high efficiency with this sort of device, you would need to distribute the nano-tubes among thin layers of the fuel, as even a sheet of paper will typically block an alpha particle.

If it works on beta-particles (which would require a different fuel than Pu-238), the layers can be thicker, perhaps as thick as aluminum foil.

It may also be possible to combine this technology with the existing thermocouple or Stirling methods to boost overall efficiency.

Betavoltaics

[denominateur]

I'm pretty sure the article is reffering to technology very similar to betavoltaic cells but with the twist of using gold as an electron source and some more strongly radioactive isotope as the energy source rather than using beta-decaying tritium directly. http://en.wikipedia.org/wiki/Betavoltaics

Fusion Power

[mweather]

Lining a fusion reactor with this stuff could go a long way toward getting more energy out than you put in.

Probably not

[Wilson_6500]

This device doesn't do anything novel when it comes to fundamental radiation interactions. What's doing most of the stopping of the radiation is the gold, since it's a dense and high atomic number material. The device's utility as a sheld, therefore, depends on the thickness of gold that incoming particles would have to penetrate on a typical path through the material. Even if space progams used gold for shielding--maybe they do, for some reason, instead of lead or uranium or steel or something--the thicknesses they would need in order to stop heavy ions and high-energy protons would probably be on the order of millimeters or centimeters, which amount to millions of thicknesses of nano-scale gold layers.

Basically, it's almost certain that a millimeter of this material would be a somewhat less effective shield than a millimeter of gold, would assumedly cost much more, but would generate probably small amounts of electricity. Even then, I don't think the original idea was to utilize ambient spaceborne radiation as the "power source" for the device.

Re:Probably not

[Stroman Rebar]

It's actually not a bad idea for part of a blended shielding solution. The fuel itself (assuming U or Pu) is a pretty high density material, although some of the daughter products might start producing significant bremsstrahlung radiation if there was too much high z material facing the cabin. Unfortunately, damage to that shielding (micrometeorite punctures or the like) would cause radiological contamination and that might outweigh the benefits.

How long before we can make them like mini zpms

[Joe The Dragon]

How long before we can make them like mini zpms

Re:I'm sorry

[Anonymous Coward]

So those who believe in the sun are damned?

phasing traditional planets out?

[reiisi]

until they master this technology enough to generate electricity solely from it and traditional planets are being phased out.

Yeah, I know you meant traditional plants, I just couldn't resist.

thermodynamics vs. thermal

[reiisi]

Thermo is not limited to thermal processes. (Yeah, that was something a high school teacher told me. Or maybe college freshman science, don't remember.)

That's all very funny

[Joseph_Daniel_Zukige]

until you consider that in a year it could be you and I that you are talking about.

FYI

[Anonymous Coward]

You do not need to put blank lines after "</blockquote>. In fact, you can put text immediately after the tag, and it will still start on a new line. For example, "text1<blockquote>text2</blockquote>text3" (typed exactly as shown, without spaces or newlines) produces "text1

text2

text3". Adding newlines after a closing blockquote tag adds extra ugly vertical space, and groups your reply to a quote with the following quote.

lead radiation absorbsion

[Anonymous Coward]

check 'lead shielding' on wikipedia.
You can't practically releflect a significant fraction of high energy nuclear radiation using matter shields - it's like reflecting machine gun bullets using tissue paper.
The energy absorbed will mostly end up as heat.

black or white

[Anonymous Coward]

for reasons having to do with convection and airflow, desert people (bedouins) wear flowing, black robes - in the sun at temperatures in the high 30's and 40's (centigrade)

Only if they use it...

[g0dsp33d]

We've had the technology to go from heat (differential) to energy for quite some time, but I'm still betting there's no Seebeck chips wired in the cooling tower. My guess is you won't see any of this stuff near a nuclear power plant any time soon either.

This isn't exactly new, is it?

[wjsteele]

I mean, we've had the International Space Station in orbit for quite a while now and it's been using this same technology... they're called "Solar Panels." They're function is almost exactly the same... they take radiation (though in a different wavelength) from the sun and convert it into electricity.

Hey, my calculator also uses a similar technology.... oh, wait... so does does my car's battery maintainer. Wow... this technology catches on fast!

Bill

Lithium hydride

[KudyardRipling]

Now that wouldn't be lithium deuteride, eh?