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Scientists Turn Nuclear Waste Into Diamond Batteries (newatlas.com)

Posted by BeauHD on from the one-man's-trash-is-another-man's-treasure dept.

Scientists at the University of Bristol have found a way to convert thousands of tons of nuclear waste into man-made diamond batteries that can generate a small electric current for thousands of years. New Atlas reports: How to dispose of nuclear waste is one of the great technical challenges of the 21st century. The trouble is, it usually turns out not to be so much a question of disposal as long-term storage. Disposal, therefore is more often a matter of keeping waste safe, but being able to get at it later when needed. One unexpected example of this is the Bristol team's work on a major source of nuclear waste from Britain's aging Magnox reactors, which are now being decommissioned after over half a century of service. These first generation reactors used graphite blocks as moderators to slow down neutrons to keep the nuclear fission process running, but decades of exposure have left the UK with 104,720 tons of graphite blocks that are now classed as nuclear waste because the radiation in the reactors changes some of the inert carbon in the blocks into radioactive carbon-14. Carbon-14 is a low-yield beta particle emitter that can't penetrate even a few centimeters of air, but it's still too dangerous to allow into the environment. Instead of burying it, the Bristol team's solution is to remove most of the c-14 from the graphite blocks and turn it into electricity-generating diamonds. The nuclear diamond battery is based on the fact that when a man-made diamond is exposed to radiation, it produces a small electric current. According to the researchers, this makes it possible to build a battery that has no moving parts, gives off no emissions, and is maintenance-free. The Bristol researchers found that the carbon-14 wasn't uniformly distributed in the Magnox blocks, but is concentrated in the side closest to the uranium fuel rods. To produce the batteries, the blocks are heated to drive out the carbon-14 from the radioactive end, leaving the blocks much less radioactive than before. c-14 gas is then collected and using low pressures and high temperatures is turned into man-made diamonds. Once formed, the beta particles emitted by the c-14 interact with the diamond's crystal lattice, throwing off electrons and generating electricity. The diamonds themselves are radioactive, so they are given a second non-radioactive diamond coating to act as a radiation shield.

39 of 156 comments (clear)

  1. Long range space probes? by Sasayaki · · Score: 5, Interesting

    Seems like this kind of technology would be very useful for long duration space probes.

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    1. Re:Long range space probes? by tburkhol · · Score: 3, Informative

      I wonder how it's output/mass compares to that of a radioactive thermal generator.

      TFA claims it can do 0.2 mW/g (vs 8 for alkaline battery). It looks like Pu-238 decay heat is around 540 mW/g, with half life of 90 years, but 90-95% of that will be lost in conversion to electricity, and it will require substantial mass for that conversion and shielding.

    2. Re:Long range space probes? by AmiMoJo · · Score: 4, Interesting

      1g of carbon apparently produces 15 Joules per day, which if you work it out is only going to deliver tens of microamperes. Enough for timekeeping and maybe running a simple LCD, perhaps even the odd very short very low power very low range radio broadcast for a sensor.

      I suppose if they includes a fairly large amount of the stuff it might generate enough energy to be useful in a space probe, but I don't think the power/weight ratio is there. You would want to use something a bit more potent if you were spending that much money, as they did with various nuclear powered probes.

      Where it will shine is for sensors. There was a plan to install sensors on water pipes before they were buried using nuclear batteries, for example. Stress sensors in buildings and on bridges. All sorts of areas where replacing the sensor is difficult and expensive so you want decades of battery life and the basic sensor isn't going to change much in that time.

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    3. Re:Long range space probes? by Gavagai80 · · Score: 2

      For an interstellar probe, where the journey could take thousands of years, this would be the only power source capable of maintaining any instruments throughout the whole flight. Of course upon reaching the destination it'd have to activate some different sort of non-degrading higher-power source to send a sufficiently-strong radio signal back to Earth.

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    4. Re:Long range space probes? by DanielRavenNest · · Score: 2, Interesting

      > Putting something radioactive on the launch pad and having it detonate in the atmosphere would be terrible too (Which is why we don't send nuclear materials into the sun.)

      That's not why we don't do it. I worked on a "Space Disposal of Nuclear Waste" study at Boeing, under contract to the DOE. The risk reduction (about two cancer deaths a year on a statistical basis) was simply not worth the extra cost (about double that of burying it underground). Also, the Sun is not the safest place to dispose of it. If your rocket fails and leaves it crossing the orbit of Venus or Mercury, they could send it back to Earth by accident. The lowest risk is to place it in an orbit halfway between Venus and Earth (0.85 AU), and that also takes much less delta-V than hitting the Sun.

      The nuclear waste was assumed to be glassified into coke-can sized segments, then formed into 2-meter "waste balls" surrounded by 20 cm thick steel alloy, which in turn was surrounded by heat shield tiles. The worst case accident is no on the launch pad, which is merely a lot of fire. The worst case is the rocket failing just before reaching orbit, where the payload kinetic energy is twice that of the best rocket fuel. So the heat shield enabled surviving re-entry, and the thick steel shell enabled surviving a terminal-velocity ground impact. It was also a corrosion-resistant alloy, because most launch failures end up dropping the payload in the ocean. We assumed a 2% launch failure rate.

      The waste balls were so damage-resistant, that the study manager would have been happy to take one home and put it in the basement to keep the house warm in the winter (they generate 2 kW from radioactive decay heat). House fires, natural gas explosions, earthquakes, none of those would do any damage to it.

  2. De Beers Marketing by 0100010001010011 · · Score: 5, Funny

    Don't get a radioactive man made diamond. Buy one of our questionably sourced ones.

    We'll even train you how to spot the difference.

    [My Mohs scale doesn't care. Minecraft has made me want a diamond everything hand tool.]

  3. Energy input. by Anonymous Coward · · Score: 5, Interesting

    What is the energy input required to create this vs the energy it will output?

    1. Re:Energy input. by wierd_w · · Score: 5, Informative

      CVD is a low pressure ionized gas crystallization process. It produces gemstone class diamonds.

      The researchers would likely benefit more from using the Russian hydraulic form compression method of producing said diamonds, because it is much cheaper. It does not produce single, large crystal diamonds without defects the way CVD does, but we aren't trying to make jewelry here. We are interested in trapping the emitted beta particles (high energy electrons emitted from the nucleus) in the lattice and using the high bandgap semi conductive properties of the diamond to transport those electrons as a reliable source of current.

      Without exact figures for how many tons of irradiated graphite there is, how energy intense CVD us compared to compressive forming, and how efficient the two end products are, I cannot even begin to answer your question though.

      Even if there is a big deficit, it might still be worthwhile, due to the immense savings on sequestration costs, and maintenance costs of these batteries.

    2. Re:Energy input. by Anonymous Coward · · Score: 4, Insightful

      The half life of Carbon-14 is 5730 years; a battery fabricated from it will produce a small current for thousands of years. Surely that has value beyond the energy input?

    3. Re:Energy input. by quanminoan · · Score: 4, Informative

      The first hydraulic presses (tetrahedral presses) were made by an american engineer Tracy Hall. The "diamond makers" is a great book that discusses these early efforts and the long history of trying to create artificial diamond. Also not sure about efficiency, but high pressure formed artificial diamonds tend to be way more defective - a problem if you're trying to create semiconductor properties of a beta voltaic. CVD actually produces diamonds with less flaws than nature.

    4. Re:Energy input. by networkBoy · · Score: 2

      Wait so we just filled in #2?

      1) Start making diamonds using CVD and marketing them as gems
      2) Sell out to DeBeers at a steep markup
      3) Profit!

      *mind blown*

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  4. Re:Can't wait to get one in my watch. by jeffb+(2.718) · · Score: 3, Informative

    You don't eat bananas, either, do you? Because those monstrosities not only turn out beta radiation, they produce nearly-impossible-to-shield gamma radiation, and they occasionally even spit particles of pure antimatter. Boo!

  5. Energy Crystals by Anonymous Coward · · Score: 3, Insightful

    So we have now created energy crystals that give off power for thousands of years.

    "Any sufficiently advanced technology is indistinguishable from magic." - Arthur C. Clarke

  6. Not that simple ... by perpenso · · Score: 5, Insightful

    What is the energy input required to create this vs the energy it will output?

    Its not that simple. Basically the true comparisons are the alternative nuclear waste storage and energy storage (battery) options?

  7. Brilliant research by quax · · Score: 4, Insightful

    This could be a real game changer if it manages to change some minds. We need nuclear tech to cope with the nuclear waste, and this can be done in an inherently safe and responsible way that turns the waste into energy.

    I very much hope this example in doing this on the small scale, as with these diamond batteries, will translate into support for bigger inherently safe designs that allow to transmute nuclear waste into lesser problems.

    1. Re:Brilliant research by Applehu+Akbar · · Score: 4, Insightful

      "This could be a real game changer if it manages to change some minds. We need nuclear tech to cope with the nuclear waste, and this can be done in an inherently safe and responsible way that turns the waste into energy."

      But take a closer look at the article. This iech only applies to reactors using graphite blocks as a moderator, a type not used in the US or Asia. The 14C is separated out from the stable 12C and formed into the energy-producing diamonds.

      Our own spent fuel, because it still contains 95% of the original energy potential, is better off being fed to a new generation of full-burnup reactors that will extract all the energy and leave behind only short-lived waste.

    2. Re:Brilliant research by AHuxley · · Score: 3, Interesting

      The UK had very different needs that just power from its reactors.
      After the US stopped sharing nuclear projects with the UK, the need for mil and public nuclear research was fully funded.
      "Information sharing ceases" https://en.wikipedia.org/wiki/...
      "End of American cooperation" https://en.wikipedia.org/wiki/...
      That has led the UK with some very different and unique production lines e.g. Sellafield/Windscale/Calder Hall, later Magnox reactors, the need for tritium production. A nice big military plutonium stockpile was created.
      Most of the UK nuclear work is now to look after old sites, keep the staff ready to build new nuclear submarine servicing in England if the other UK sites won't stay open.

      --
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    3. Re:Brilliant research by quax · · Score: 2

      Agreed. Hence my emphasis on changing minds. To me this technology is not so much a large scale practical solution, but something that will hopefully teach a new generation that nuclear energy can be handled responsibly. (And to me that means inherently sub-critical).

  8. Re:Can't wait to get one in my watch. by fuzzyfuzzyfungus · · Score: 2

    We did go through a period of nuclear powered pacemakers. Plutonium 238 radiothermal was apparently the most popular.

    It's considered good practice to remove them before cremation; but there are surprisingly few unpleasant stories.

  9. Fine, power your bitcoin asic ... by perpenso · · Score: 3, Informative

    Carrying around a tiny radioactive battery in every phone, watch, pacemaker, and remote control seems like a great idea,

    Fine, power your bitcoin asic in the closet.

    Or move the remote control a few centimeters away from you when not actively clicking.

    From the summary: "Carbon-14 is a low-yield beta particle emitter that can't penetrate even a few centimeters of air"

    1. Re:Fine, power your bitcoin asic ... by jcochran · · Score: 5, Interesting

      You gotta remember that you're dealing with idiots who tremble at even a hint of an idea that radiation is near them. In fact, there's a little device in your car (assuming it's powered by gasoline) where it's name was determined due to the fear of radiation. The "catalytic converter" has that name because of idiots who fear the concept of radiation. The correct proper name for that device is "catalytic reactor". But the word reactor is used in nuclear reactors so "obviously" a "catalytic reactor" is dangerously radioactive and should never ever be placed in a car because it might spread radiation all over the place and don't even think about what would happen in an accident. Because of that fear, engineers call that little device a "catalytic converter" because that doesn't have the dangerous radiation inducing effects that the word "reactor" has.

      Remember your audience and compensate for their ignorance and/or stupidity.

  10. Carbon-14 by jbmartin6 · · Score: 2

    This waste is really going to screw with any future archaeologists, let's put some of it in all our grade school time capsules.

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    1. Re:Carbon-14 by srmalloy · · Score: 2

      Not really, because the carbon-14 dating relies on there being an approximately stable level of that isotope in the environment to be taken up by biologic processes, and this production of nuclear batteries isolates the carbon-14 from the environment.

  11. Re:Can't wait to get one in my watch. by Dutch+Gun · · Score: 2

    Hulk love bananas!

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  12. Hmmmmmm by JustAnotherOldGuy · · Score: 2

    Sounds too good to be true....but let's see what comes of it.

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  13. Real electricity from diamonds! by Billy+the+Mountain · · Score: 3, Informative

    Yes it is electricity BUT it's measured in picoamps.

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  14. Crush the diamond and the SNORT it by raymorris · · Score: 2

    As the summary mentioned, the radiation from most waste can't penetrate even air, or tissue paper. So to have a problem you'll need to crush it, then snort it up your nose like cocaine.

  15. Energy density by lorinc · · Score: 4, Interesting

    What's the recoverable energy density of this? I mean, how many watts of electricity can I get out of on of these, for how long, per cm^3?

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    1. Re:Energy density by ezdiy · · Score: 2

      You don't want to care about energy density (aka capacity), as that number is insane for anything nuclear. You do want to know the internal resistance, rate of "discharge", basically watts it can produce for given weight. You can burn uranium or gasoline in an instant, but decay mode sources (RTG and this) are limited to rate of decay.

      Back of envelope: (all exponents are to power of 10, not 2).

      One C-14 atom decays in 5730 years, shoots off 156476 electron volt we ideally capture, and one anti-neutrino we shield off
      One electron volt is 1.6e-19 J, ie that beta decay is roughly 2.5e-14 J.

      You need 10^14 atoms of c-14 to get 2.5 joule every 5730 years.

      Now for watts (aka joule per second): 5730 * 360 * 86400 * 10^14 to get 2.5 watts output
      5730 * 360 * 86400 * 10^14 / 2.5 =

      7.1e24 C-14 atoms per watt.

      Now C-12 atom supposedly weights 2e-23 grams and C-14 should be in same ballpark, meaning

      35 grams of this stuff, in ideal case gives off 1watt,

      Which is pretty impressive, for a battery which lasts basically forever.

  16. Unlike my high maintenence mechanical batteries... by 91degrees · · Score: 2

    this makes it possible to build a battery that has no moving parts, gives off no emissions, and is maintenance-free

    Okay, I'm not criticising the basic idea here, but this list of benefits applies to all batteries.

  17. Re:Can't wait to get one in my watch. by Jon+Peterson · · Score: 2

    I have a watch from the 1940s that's still giving out plenty of radiation. Sadly, the phosphor is all used up so it doesn't glow at all.

    Early glow in the dark paints used a mixture of radium and phosphor. The decay from the radium would excite the phosphor and make it glow. Unfortunately it also broke down the phosphor, so while radium lasts for centuries, the paint doesn't.

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  18. Re:Can't wait to get one in my watch. by sjames · · Score: 2

    Actually, in a study of nuclear medicine technicians, it was fould that their mortality rate was slightly lower than others in healthcare who didn't get the exposure. It seems there's a sweet spot for radiation exposure and background radiation in many places is just a bit below it.

  19. Re:Unlike my high maintenence mechanical batteries by drinkypoo · · Score: 2

    this makes it possible to build a battery that has no moving parts, gives off no emissions, and is maintenance-free

    Okay, I'm not criticising the basic idea here, but this list of benefits applies to all batteries.

    False. Moving parts, OK. But emissions? Google up on car battery explosions. And maintenance free? Google up some more on car batteries. In fact, if you don't maintain them when they have emissions, it makes them more likely to explode.

    There are numerous batteries which are not just lumps which spit out power.

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  20. Re:Can't wait to get one in my watch. by drinkypoo · · Score: 2

    Personally I have never to my knowledge been in the presence of a radioluminescent anything.

    They're not actually that hard to come by, you can buy radioluminescent keychains and you've probably stood next to someone with one in their pocket more than once without knowing it. You used to be able to buy tritium vial lights readily in the USA and you can still get them easily in the UK and other places.

    --
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  21. Re:Unlike my high maintenence mechanical batteries by 91degrees · · Score: 2

    Okay. Point taken. Although I'd really consider explosions to be a separate issue from emissions. And not exploding sounds like one of the legitimate advantages of these; the other key one being longevity.

  22. Do people actually know rough performance? by 91degrees · · Score: 2

    It sounds like we're looking at expensive components, and other posts suggests picoamps. But what sized battery would we need to get that to something usable?

    Do these have a potential use in satellites or are they too heavy? How about pacemakers? Or is the radiation shielding inadequate?

    1. Re:Do people actually know rough performance? by 91degrees · · Score: 2
      Answering my own question - digitaltrends gives us some information.

      A diamond beta-battery containing 1g of C14 will deliver 15J per day, and will continue to produce this level of output for 5,730 years

      So that's 170 microWatts per gram or 6 grams per milliwatt. That's actually a usable level of power even when talking such small power cells. Still not sure what a good application might be for this technology.

  23. Re:Can't wait to get one in my watch. by jeffb+(2.718) · · Score: 2

    From a bit of googling, they'd use Radium-226, which is an alpha-emitter. Thinking a bit of crystal covering the dial, and a metal frame, and you're sorta safe, no?

    Yes, you, the wearer of the intact watch, were completely safe; its housing would stop alpha radiation at effectively 100%.

    The people who drew up the radioactive paint using mouth-operated pipettes, and the people who scavenged through the trash containing the smashed watch bits, not so much.

  24. Re:Can't wait to get one in my watch. by sjames · · Score: 2

    overview. Also here and here.

    Finally, here.

    Please be a bit more careful where you throw that bullcrap. And WASH YOUR HANDS!