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NASA Developing Nuclear Reactor For Moon and Mars

Posted by CmdrTaco on from the react-to-the-reactor dept.

Al writes "NASA recently finished testing a miniature nuclear reactor that would provide power for an astronaut base on the Moon or Mars. The reactor combines a small fission system with a Stirling engine to make a 'safe, reliable, and efficient' way to produce electricity. The system being tested at NASA's Glenn Research Center can produce 2.3 kilowatts and could be ready for launch by 2020, NASA officials say. The reactor ought to provide much more power than solar panels but could prove controversial with the public concerned about launching a nuclear power source and placing it on the Moon or another planet."

10 of 424 comments (clear)

  1. Nuclear Power on the Moon FTW! by morgan_greywolf · · Score: 4, Interesting

    Nuclear power is actually one of the safest, cleanest, and most reliable forms of power ever invented. So long as no meteroites hit it, we should be fine. Huh. Wonder what caused all those craters on the moon.....

    --
    My blog
  2. That's only 20 Amps at 115V by ameline · · Score: 3, Interesting

    That's one standard kitchen outlet in North America. You could run a coffee maker and a microwave, but not a whole lot more...

    How much does it weigh in total (including shielding etc)?

    --
    Ian Ameline
    1. Re:That's only 20 Amps at 115V by vlm · · Score: 3, Interesting

      40 kW is approximately 17 outlets that can handle 20 A at 115 V.

      So, if all they ran were grow lights, that would be about 30 grow lights? I'm thinking that is not enough to grow the food for even one person during the lunar night. Assuming all you did with your electricity was grow some chow. I think one grow light's worth of plants is not enough for one persons daily food intake, and you're not going to grow a crop in rotation 30 days.

      True, you've got plenty of light during the long lunar day, maybe it would be possible to do reduced light for 8 hours to 3 plants, but thats probably going to screw up the growth cycle of ... anything?

      Hmm. So if you electrolyze water at a rate of 40 kW, and the average human needs about 3 Kg a day (rounded up) how many people can breathe? Of course you also need life support to freeze the CO2 out of the atmosphere, and some way to turn that CO2 into C and O2 or into plant matter.

      No, I'm thinking you need well over 40 KW per person for a sustainable moon colony.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    2. Re:That's only 20 Amps at 115V by nasor · · Score: 3, Interesting

      The linked article doesn't really communicate the selling point, which is that these reactors are very small; the whole thing fits in a roughly 1 x 2 meter package (larger when you deploy the fold-radiators). It's true that one wouldn't be enough to power a large base, but NASA isn't planning anything like a base with a greenhouse for growing food - these things are basically meant to provide power for the astronaut's lander/trailer when it's dark outside. They just need to run the life support systems and radios.

  3. Why the west is doomed by tjstork · · Score: 3, Interesting

    All of our inhibitions about nuclear power is why we are doomed. Actually even wrote about this previously... the real danger to the west is not nuclear proliferation from atomic bombs, but from third world countries adopting nuclear mining, nuclear aircraft, nuclear ships, and nuclear spacecraft and pretty much leaving the west behind in a windmill driven green feel good stone ages.

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    This is my sig.
  4. If you're taking a reactor anyway... by MozeeToby · · Score: 5, Interesting

    Why not re-open research into nuclear thermal rockets? They were able to get them up to 40% efficiency back in 1972, I'm would hope we can do better than that now. Use the reactor to heat a propellant to get you to the moon, then use the reactor on the moon to power the base. If it's time to head home, you only need to ship a relatively stable propellant up, rather than actual rocket fuel.

  5. Re:mmhmmm by ae1294 · · Score: 3, Interesting

    Solar panels are great until they get dirty or worse damaged by micro-meteorites. Plus you might not have light 24/7 when you are on a large body like mars so you gotta add lots of batteries for your Solar panel setup unless you're ok with only breathing during the day...

  6. Why not expoit temperature by kawabago · · Score: 3, Interesting

    Why isn't NASA looking into technology to exploit the temperature difference between lit and shaded areas on the moon to generate electricity? That should be an excellent source of power most of the time.

  7. Re:WHere do they put the heat? by vlm · · Score: 3, Interesting

    Ok, great, they put the heat in one side of the Sterling Cycle Engine, and it moves to the other side and we get motion, but what do they do with the heat? There's no air/water to bump against a cooling fin to get the activity of the molecules. Does the "icy vacuum of space" actually cool things very well?

    Yeah, it does. An infinitely large radiator protected from the sun and from the surface would cool to around 2.7 degrees kelvin, pretty chilly. When you understand why it won't cool any further, then you'll know a lot more than you need for this engineering problem, although it is interesting. There are engineering limitations where adding another kilometer of radiator tubing to drop from 4K to 3K just isn't worth the cost of tubing, and/or the power required to pump the refrigerant thru the tubes. Radiation power increases as a pretty high power of temperature.

    If it did, why wouldn't a sterling cycle engine with one side in the shade and one side in the sun work pretty darn well anyhow?

    Look up the rotation period of the moon. Very roughly, Dark for 2 weeks, Light for 2 weeks. Unless you make a engine thats about 1/2 the circumference of the moon (or, just the diameter, if you were REALLY hard core). Which is not totally out of the question, although it would be a heck of an amazing civil engineering project.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  8. 8 years isn't that much by thasmudyan · · Score: 3, Interesting

    On an outpost that is hopefully* going to be permanently manned, 8 years seems a little short sighted. And if we're honest with ourselves, even those 8 years are not a realistic estimate. Consider that this thing has lots of movable parts and a very volatile coolant system all of which needs to withstand the extraordinary stress of launch and landing.

    Consider RTGs on the other hand. They have no moving parts, a much longer lifespan, and a very well known failure mode (continuous degradation of the fission core and thermoelectric elements). While they do degrade considerably over several decades, they do not ever need maintenance and they don't fail suddenly like this very expensive and complex reactor will. Of course 40kW is an energy budget that could only be satisfied by several of these modules, but on the plus side this would promote a decentralized power architecture for the presumed offworld base. The reactor behemoth on the other hand will just fail spectacularly one day (probably after a long series of notorious problems that started on launch day) and Earth will need to ship a fucking big replacement package all the way up there while the Mars ground crew sits in the dark and with minimal life support, taking very shallow breaths.

    * the reason I use that word here is because we probably will have just one phenomenally expensive mission that lasts a few weeks at the outset and after that we won't ever go there again. If the Moon mission era is any indication.