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Material Converts Radiation Into Electricity

Posted by kdawson on from the don't-irradiate-me-bro dept.

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."

4 of 146 comments (clear)

  1. Re:Why is it... by pla · · Score: 2, Informative

    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.

  2. Re:Waste...? by BlueParrot · · Score: 4, Informative

    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.
  3. Probably much less efficent than steam by erice · · Score: 2, Informative

    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.

  4. Betavoltaics by denominateur · · Score: 2, Informative

    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