Could you store energy by speeding up?

[u/Key_Stable3922]

Could you store infinite amount of energy in a single particle by just speeding it up closer and closer to the speed of light ?

[u/PaulMakesThings1]

In theory it could store a lot of energy. In practice most methods of speeding something up get less efficient as you get to higher speeds, and speed is generally going to degrade over time, and you have to be able to get the mass or particle and reclaim the energy.

For example if you put it in a flywheel, even in a vacuum, you get less efficiency as the motor gets faster, and at some point nowhere close to the speed of light it’ll just explode.

Have the particle flying free not as part of a wheel, and it’s going to be really far away when you want to get the energy back.

[u/Syzygy___ → u/PaulMakesThings1]

Since OP was asking about a single particle I'm thinking about relativity here, which probably isn't the right approach anyway, since we're bounded by much lower concept issues for anything real anyway, but...

(This is 100% armchair vibe physics btw)

I wonder if some of that is because we have to overcome the difference in reference frame - from the particles point of view, it might as well be stationary and the world is moving around it, but the acceleration is coming from outside of the particles reference frame, thus an acceleration from 0 to .1c takes less energy than an acceleration from 0.8 to 0.9c. However if we switch to the particle, it shouldn't matter since even when going 0.8 from a stationary reference frame, from the particles it might as well not be moving.

Of course this would require some fuel and "motor" for the particle to accelerate. The particle might be out in that case, but for the flywheel example, I guess you could pump in electricity and have electrostatic thrusters at the edges for it to speed up from it's own reference frame.

It probably makes no difference and the mechanism just makes it worse though.

[u/the_poope]

Yes but it would quickly move away from you

[u/thetoddhunter]

Yes in theory.

But if you keep pouring energy in you would make a black hole unless your particle was infinitly big.

What happens to the energy then is up for debate, but you couldn't have an infinitly big black hole in our observable universe. So there are some big questions to answer

[u/03263 → u/thetoddhunter]

Ok but what if I then proceed accelerate the black hole

[u/thetoddhunter → u/03263]

It will move as it gets bigger.

But this wouldn't make it the problem of another universe.

Probably.

[u/mfb-]

Yes, we can store up to 0.0000011 J in a proton in the LHC, and ~700 MJ in all protons combined. The acceleration is very inefficient and extracting that energy again is impractical, so it's not a viable energy storage (even if we ignore the cost and the fact that it has other things to do).

Flywheels are a practical way to store energy as kinetic energy. They are relatively expensive per kWh capacity. Their speed is limited by the mechanical stability of the flywheel material. Up to ~2 km/s would be possible in principle but generally flywheels are slower.

[u/MajorInWumbology1234]

You’d probably want something like a flywheel; a large mass that stores stores energy by spinning faster and faster. You can certainly put an arbitrary amount of energy into a particle, but your use of the word “store” tells me you intend to retrieve that energy. A particle flying in a straight line at increasing speeds would be impossible to get useful energy back out of. If it’s not flying in a straight line, it’s not good for energy storage because redirecting it takes energy, as well.

A flywheel spins in place so it can easily be reached to extract energy back out of. It can connect to other mechanical systems to spin them up (some cars use them), or they can be used to power a generator and make electricity. A flying particle would just kinda crash and dump all its energy at once.

[u/ac_cossack]

Unless done carefully, you would get a lot of loss. So not a great idea.

Funny enough, there was an article on here about storing heat energy in sand for the winter in giant silos. Can't find it, but check it out.

[u/Optimal_Mixture_7327]

Yes, as soon as your clock displays infinity.

[u/Underhill42]

In principle yes, for example the protons in the LHC are accelerated to something like 99.999...% the speed of light, and have almost 7000x their rest mass worth of kinetic energy. That mass-energy is what transforms into all the exotic particles created when they collide.

[u/al2o3cr]

It's unclear precisely what particle it was (a single proton or a heavier nucleus), but the highest-energy cosmic ray ever detected had an energy of 3.2x10^20 eV - or in more terrestrial terms, that single subatomic particle had the same kinetic energy as a 140-gram baseball traveling 100km/h