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The Mars rovers Perseverance and Curiosity use RTG to generate power and they move slowly... Does it produce enough enery so that we can use it on electric cars that go fast?

And will the cars go fast or slow?

Đαrkraι
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  • Does this answer your question? https://space.stackexchange.com/q/50282/4704 – Schwern Mar 08 '21 at 08:08
  • unfortunately no, i need more details :) – Đαrkraι Mar 08 '21 at 09:09
  • It's not very practical to use a RTG for a car. See https://space.stackexchange.com/q/50047/38535 – PM 2Ring Mar 08 '21 at 09:23
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    @C0D3X what details do you need that the answers to those questions lack? – Starfish Prime Mar 08 '21 at 10:04
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    I'd imagine it would be much more efficient if it was used to generate heat directly (passing it to a coolant) and utilize it in e.g. Stirling engine for propelling the car. The thermocouple could be there to provide electricity for assorted general needs like headlights, dashboard, AC etc. The thermocouple is an awfully wasteful method of tapping into the nuclear energy of the RTG, The only reason it's used is because it's extremely fail-proof - no moving parts, no working liquids, no leaky interface through the anti-artillery grade casing. – SF. Mar 08 '21 at 10:59
  • @SF. looks like they have got nuclear thermal systems down to 500kg for a couple of hundred kW thermal power, so you could in theory make a car like object with a turbine of some sort that had actual street car speeds. Supercars are up closer to a Mw so still not actually going to be 'fast'. – GremlinWranger Mar 08 '21 at 11:30
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    @GremlinWranger I'd say a car that never requires recharging or refueling has its appeal, even with underwhelming engine power. – SF. Mar 08 '21 at 11:37
  • The question title does not match the body. The body is a duplicate of a previous question. The title would be a new question, however. – DrSheldon Mar 08 '21 at 12:11
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    Voting to close as a duplicate of Can we power things (like cars or similar rovers) on earth in the same way Perseverance generates power? The fact that 'you need more details' doesn't mean that the question isn't a duplicate. That "does this answer your question" thing is an unfortunately phrased autogenerated comment – Organic Marble Mar 08 '21 at 13:56

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Does it produce enough enery so that we can use it on electric cars that go fast?

An RTG can be used to produce electricity. You can do whatever you like with that electricity. You could, for example, use it to charge the batteries in an electric car. This is exactly what is done on eg. Perseverance... batteries are used for things which have a power draw exceeding that which the RTG can deliver (which includes, I believe, driving around).

The RTG on the big Mars rovers generates about 110W continuously. Something like a Chevrolet Volt has a ~18kWh battery pack. Assuming you're getting 110W of electrical power out of the RTG and you have a magical 100% efficient charging system, you could charge up the battery in a little under a week, and then drive ~80km before you ran out of charge. At which point you could wait for another week for the battery to charge up.

One could imagine a larger RTG containing more unstable radioisotopes that has a shorter lifespan but a higher power output, perhaps. It might charge your car in less than a week.

Or alternatively you could charge it up in almost any other way, such as with a small array of solar panels, that would probably be more effective and would not have all the associated issues with having a large slab of toxic radioactive waste in your garage.

Starfish Prime
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  • Possibly worth adding that the RTG used for the Mars Rovers is 45kg overall, with that Chevrolet Volt battery pack weighing 197kg. So while you can swap one battery bank for 4 RTGs and get 440 watts/0.44kw the car needs around 10kw to get sustain 60kmh on the flat so even then it isn't going to be fast. – GremlinWranger Mar 08 '21 at 11:13
  • @GremlinWranger you could fill those four RTG with Po-210 instead of boring old Pu-238 and get enough power, at least for a month or two, before the activity drops and you can no longer run the engine at max. 800g of Po-210 costs a wee bit more than 200kg of lithium cells, though... – Starfish Prime Mar 08 '21 at 11:40
  • @StarfishPrime Just don't get into an accident. – Schwern Mar 08 '21 at 19:02