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I really wanted this to be about Rolls-Royce Motor Cars Limited rather than Rolls-Royce Holdings plc. A nuclear-powered Rolls-Royce Phantom would be incredibly

I really wanted this to be about Rolls-Royce Motor Cars Limited rather than Rolls-Royce Holdings plc. A nuclear-powered Rolls-Royce Phantom would be incredibly boss.

LeoPanthera 7y ago
Would a nuclear powered EV ever need refuelling?
- brnt 7y ago
  I remember Toshiba having a decay-based laptop battery in development (at least 10 years ago, maybe 20). You wouldn't have to charge, ever. Now that would be something!
  - Stratoscope 7y ago
    When I was five or so, I had a watch with a radium dial. I read in a kid's science book that if you went to bed and waited until your eyes were adjusted to the dark, and then held the watch dial against your closed eyelid, you would be able to see the sparks as individual radium atoms decayed. I did this, and it worked! I could see each spark!
    - missosoup 7y ago
      Radium is primarily an alpha emitter. Alpha won't cross through the glass of the watch face, or even your skin. Maybe you were seeing the much more rare beta decays.
      - FiatLuxDave 7y ago
        I doubt it was from the betas, they are all fairly low energy for typical radium. It was probably from the gammas produced by Ra-226. Ra-226 produces a 186 keV gamma in 3.3% of decays. Cherenkov radiation flashes in the eye are observed by patients undergoing clinical radiation therapy (see this interesting paper where this was explored and tested: https://www.redjournal.org/article/S0360-3016(19)33947-1/fulltext https://www.redjournal.org/article/S0360-3016(19)33947-1/ful... ). The test done in the paper was with much higher energy gammas, but it is feasible that the 186 keV lines could cause the same effect. I've never observed this when working with radium, but then I don't stick it in my eye.
    - edm0nd 7y ago
      I remember reading some witness accounts who saw nuclear explosions and they described being able to see through their eyelids (when closed) and in some cases even through their hands. Pretty wild when you think about how bright and forceful a nuclear explosion is.
    - kmano8 7y ago
      Ball watches use Tritium in glass tubes for some really incredible lume https://shop.ballwatch.ch/en/ https://shop.ballwatch.ch/en/
- DaiPlusPlus 7y ago
  If it were a radioisotope thermoelectric generator, then probably yes.
  - mkl 7y ago
    I don't think that would generate enough power for a car. See maximum output of some here: https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
    - jacobush 7y ago
      Sure it would. Couple it with a lion - battery as a buffer. A tiny pellet gives 60 watts of heat. A heat cycle engine could recover maybe 10 watts of that. Put 500 pellets in there and you could get 5kw or so electric charge, all the time. Of course the pellets are insanely toxic in just about every way.
      - mkl 7y ago
        Are you sure? If I'm reading the "Terrestrial" table on that Wikipedia page right, 5kW of electrical power would need an RTG weighing many tonnes, significantly more than a bus.
        jacobush 7y ago
        These things are thermocouples. I’m referring to heat engines, like turbines, which are much more efficient
      - VLM 7y ago
        The problem with the related 25 KW of 24x7 waste heat is that'll eventually melt the very heavy several inches of lead unless very carefully cooled or distributed. Even 20 watts will eventually melt small quantities of metal, think of every soldering iron. The authorities are not going to approve a reactor that melts its own armor if someone accidentally throws a quilt on top or equivalent. So most designs do some kind of incredibly heavy passive cooling where the required very large surface of the armor only emits a fraction of the heat you'd see from sunlight. Now sunlight as an engineering 1 sig fig estimate is about a kilowatt per sq meter, so your 25 KW of waste heat would require some multiple of 25 square meters of surface area for passive safety cooling. A cube 5 meters on a side of solid copper and lead would have a surface area of 150 square meters, which will be warm to the touch but not as warm as it would get laying in the sun all day. The problem with a cube of lead and copper 5 meters on a side is that is 125 cubic meters. And metal, again to one sig fig, weighs about ten thousand kilos per cubic meter. So that shielding would weigh quite a lot. Its the old problem of the ratio of surface area to volume that comes up in so many engineering problems. Yeah I'm strong enough that I could pick up a small space craft RTG and walk around with it, for several reps at the gym anyway, but the scaling factors are such that a car charger would be immensely heavy. I'm not sure, on a daily basis, what you'd do with 125 kilowatt-hours of car charge anyway. A gallon of gas is about 25 KW-hr (to one sig fig) so that's five gallons of gas. That would be 150 miles of driving per day, around here that would be something like 3 to 5 hours of driving per day, which sounds like a horrible way to live. Unless you're a bus driver, or delivery guy, or similar, LOL of course. Still, I don't think a five meter on a side bus or car is in our future.
- TeMPOraL 7y ago
  It'd probably need to replenish the liquid (e.g. water) used for reactor cooling/energy extraction.
  - LeonM 7y ago
    I don't know about the thermal efficiency of a small nuclear reactor, but I imagine you could probably make that a closed loop system. Just as you would on an internal combustion engine, with a radiator to cool/condense the heated coolant.
    - TeMPOraL 7y ago
      Even in an ICE, you have to replenish/change the oil and cooling fluid; I'd expect a closed-loop small nuclear reactor to be similar in this regard. Still, replenishing something every couple months is much better than refueling or recharging.
- throw0101a 7y ago
  Well Doc Brown had to put in banana peels and some flat beer, so I'd say yes: * https://www.youtube.com/watch?v=ptlhgFaB89Y https://www.youtube.com/watch?v=ptlhgFaB89Y
LeonM 7y ago
Actually, several American car manufactured experimented with this idea in the 50's. Most notably Ford with the Nucleon [0], but also other brands such as Packard and (I believe) Cadillac were also designing nuclear powered cars. Eventually it was concluded that the shielding of the reactor would make a nuclear powered passenger car impractical, as it would make the vehicle too big. And of course there were the obvious safety concerns. There is an good documentary on this subject on youtube [1]. [0] https://en.wikipedia.org/wiki/Ford_Nucleon https://en.wikipedia.org/wiki/Ford_Nucleon [1] https://www.youtube.com/watch?v=kR5gefU87TY https://www.youtube.com/watch?v=kR5gefU87TY
- peteradio 7y ago
  Maybe that "too big" argument should be revisited in light of recent standard sizes.
NeedMoreTea 7y ago
It's probably the only possible successor to that surprisingly standard looking Merlin powered Phantom II someone did a few years ago.
throw0101a 7y ago
I'm still waiting for my Mr. Fusion.

I really wanted this to be about Rolls-Royce Motor Cars Limited rather than Rolls-Royce Holdings plc. A nuclear-powered Rolls-Royce Phantom would be incredibly boss.

LeoPanthera 7y ago

Would a nuclear powered EV ever need refuelling?

brnt 7y ago
I remember Toshiba having a decay-based laptop battery in development (at least 10 years ago, maybe 20). You wouldn't have to charge, ever. Now that would be something!
- Stratoscope 7y ago
  When I was five or so, I had a watch with a radium dial. I read in a kid's science book that if you went to bed and waited until your eyes were adjusted to the dark, and then held the watch dial against your closed eyelid, you would be able to see the sparks as individual radium atoms decayed. I did this, and it worked! I could see each spark!
  - missosoup 7y ago
    Radium is primarily an alpha emitter. Alpha won't cross through the glass of the watch face, or even your skin. Maybe you were seeing the much more rare beta decays.
    - FiatLuxDave 7y ago
      I doubt it was from the betas, they are all fairly low energy for typical radium. It was probably from the gammas produced by Ra-226. Ra-226 produces a 186 keV gamma in 3.3% of decays. Cherenkov radiation flashes in the eye are observed by patients undergoing clinical radiation therapy (see this interesting paper where this was explored and tested: https://www.redjournal.org/article/S0360-3016(19)33947-1/fulltext https://www.redjournal.org/article/S0360-3016(19)33947-1/ful... ). The test done in the paper was with much higher energy gammas, but it is feasible that the 186 keV lines could cause the same effect. I've never observed this when working with radium, but then I don't stick it in my eye.
  - edm0nd 7y ago
    I remember reading some witness accounts who saw nuclear explosions and they described being able to see through their eyelids (when closed) and in some cases even through their hands. Pretty wild when you think about how bright and forceful a nuclear explosion is.
  - kmano8 7y ago
    Ball watches use Tritium in glass tubes for some really incredible lume https://shop.ballwatch.ch/en/ https://shop.ballwatch.ch/en/
DaiPlusPlus 7y ago
If it were a radioisotope thermoelectric generator, then probably yes.
- mkl 7y ago
  I don't think that would generate enough power for a car. See maximum output of some here: https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
  - jacobush 7y ago
    Sure it would. Couple it with a lion - battery as a buffer. A tiny pellet gives 60 watts of heat. A heat cycle engine could recover maybe 10 watts of that. Put 500 pellets in there and you could get 5kw or so electric charge, all the time. Of course the pellets are insanely toxic in just about every way.
    - mkl 7y ago
      Are you sure? If I'm reading the "Terrestrial" table on that Wikipedia page right, 5kW of electrical power would need an RTG weighing many tonnes, significantly more than a bus.
      - jacobush 7y ago
        These things are thermocouples. I’m referring to heat engines, like turbines, which are much more efficient
    - VLM 7y ago
      The problem with the related 25 KW of 24x7 waste heat is that'll eventually melt the very heavy several inches of lead unless very carefully cooled or distributed. Even 20 watts will eventually melt small quantities of metal, think of every soldering iron. The authorities are not going to approve a reactor that melts its own armor if someone accidentally throws a quilt on top or equivalent. So most designs do some kind of incredibly heavy passive cooling where the required very large surface of the armor only emits a fraction of the heat you'd see from sunlight. Now sunlight as an engineering 1 sig fig estimate is about a kilowatt per sq meter, so your 25 KW of waste heat would require some multiple of 25 square meters of surface area for passive safety cooling. A cube 5 meters on a side of solid copper and lead would have a surface area of 150 square meters, which will be warm to the touch but not as warm as it would get laying in the sun all day. The problem with a cube of lead and copper 5 meters on a side is that is 125 cubic meters. And metal, again to one sig fig, weighs about ten thousand kilos per cubic meter. So that shielding would weigh quite a lot. Its the old problem of the ratio of surface area to volume that comes up in so many engineering problems. Yeah I'm strong enough that I could pick up a small space craft RTG and walk around with it, for several reps at the gym anyway, but the scaling factors are such that a car charger would be immensely heavy. I'm not sure, on a daily basis, what you'd do with 125 kilowatt-hours of car charge anyway. A gallon of gas is about 25 KW-hr (to one sig fig) so that's five gallons of gas. That would be 150 miles of driving per day, around here that would be something like 3 to 5 hours of driving per day, which sounds like a horrible way to live. Unless you're a bus driver, or delivery guy, or similar, LOL of course. Still, I don't think a five meter on a side bus or car is in our future.
TeMPOraL 7y ago
It'd probably need to replenish the liquid (e.g. water) used for reactor cooling/energy extraction.
- LeonM 7y ago
  I don't know about the thermal efficiency of a small nuclear reactor, but I imagine you could probably make that a closed loop system. Just as you would on an internal combustion engine, with a radiator to cool/condense the heated coolant.
  - TeMPOraL 7y ago
    Even in an ICE, you have to replenish/change the oil and cooling fluid; I'd expect a closed-loop small nuclear reactor to be similar in this regard. Still, replenishing something every couple months is much better than refueling or recharging.
throw0101a 7y ago
Well Doc Brown had to put in banana peels and some flat beer, so I'd say yes: * https://www.youtube.com/watch?v=ptlhgFaB89Y https://www.youtube.com/watch?v=ptlhgFaB89Y

LeonM 7y ago

Actually, several American car manufactured experimented with this idea in the 50's. Most notably Ford with the Nucleon [0], but also other brands such as Packard and (I believe) Cadillac were also designing nuclear powered cars. Eventually it was concluded that the shielding of the reactor would make a nuclear powered passenger car impractical, as it would make the vehicle too big. And of course there were the obvious safety concerns. There is an good documentary on this subject on youtube [1]. [0] https://en.wikipedia.org/wiki/Ford_Nucleon https://en.wikipedia.org/wiki/Ford_Nucleon [1] https://www.youtube.com/watch?v=kR5gefU87TY https://www.youtube.com/watch?v=kR5gefU87TY

peteradio 7y ago
Maybe that "too big" argument should be revisited in light of recent standard sizes.

NeedMoreTea 7y ago

It's probably the only possible successor to that surprisingly standard looking Merlin powered Phantom II someone did a few years ago.

throw0101a 7y ago

I'm still waiting for my Mr. Fusion.