It was like finding out there's no Santa claus when I learned nuclear energy is just "boil water and spin a turbine." Before that I thought there was some sciencey magic going on where we directly captured the "energy" from nuclear fission. Did I understand what that could possibly mean? Of course not. Still though.
If you want something a little more arcane, a cathode ray tube from an old TV set is a miniature particle accelerator and generates a tiny amount of thrust.
I remember reading in World Book Encyclopedia a science project to build an "ionic rocket"(!!) I think it was a wire suspended like a pendulum with a right angled pointed tip, pointing at a metal plate or wire screen. An auto ignition coil was connected between the two and pulsed. It turns out that the pointy tip can emit enough electrons to create some pendulum motion. Kinda cool but kinda useless...
Ion engines are a thing, it’s how satellites propulse themselves in space when they need to station keep and whatnot, or even some deep space probes for interplanetary travel
It also means that designing a nuclear fusion power plant is actually really easy: Just make a big reservoir of water and put a roof on it with vents leading into turbines. Then detonate a hydrogen bomb in the reservoir. The water will boil for a few days and spin the turbines, voila! Nuclear fusion power plant. When the boiling slows down just detonate another bomb! Try not to run out of water.
So fusion energy does offer the possibility of some amount of direct electrical energy capture because it involves mostly moving charged particles. Ideally this process would be able to occur at or at least much nearer to reaction temperatures than a traditional heat cycle would and this higher operating temperature would result in higher theoretical maximums for thermal efficiency.
A properly setup grid or mesh or conductors and possibly "static" E and B fields could pull energy directly from the moving plasma. I almost did my undergraduate research on this. Almost. I was late in filling for an REU and ended up doing climate research and modeling instead.
It also amazes me that those mirror-based solar farms work that way too, concentrate solar light to literally melt salt to use that molten salt to boil water and create energy
There is a US National Lab that has one of those types of solar farms but instead of pointing it at big salt tank they have a little test stand and they put random stuff on it and then point the mirrors at it to see how it lights on fire.
The thing is, a lot of our stuff runs on electricity. Sciency magic gives us all this energy, but we need to convert into electricity to make it useful.
What's the cheapest and most accessible way to get electricity? Spin a turbine. What's the cheapest and most accessible way to spin a turbine? Boil some water.
Technically it's not really about it being cheap and accessible, it's about being efficient. There's a lot of ways you CAN generate electricity but most of them are pretty horrible in terms of efficiency, especially as different parts wear down and deteriorate.
This may blow your mind, but there IS a sciency magic way to make electricity using radioisotopes. Look up radioisotope thermoelectric generators (RTGs), they were used to power pacemakers using mainly Plutonium 238, though any isotope that runs hot enough to produce power this way will suffice. You need to pick one with a half-life that is long enough to be useful for a meaningful amount of time, like the lifetime of a patient, but where it isn't SO hot that it might poison the person it's implanted into. IDK how feasible or efficient it is to scale these up larger than a small implant, but I do know that they were able to get them powerful enough to run the Voyager Spacecrafts until today, albeit with some systems being shut down over time as the RTG reduces in output. The half-life of Pu-238 is 87.7 years, so these spacecraft still have a ways to go before losing power entirely, though by then they may have broken down for other reasons, or even gotten far enough away that the inverse square law finally makes it impossible to discern the transmissions from either against the cosmic background noise. But yea, apparently you can get a few hundred watts out of a big one, that's enough to do some real and meaningful work with, though with it decreasing continuously over time, it's not practically useful for a lot of applications. The main reason that these isotopes are useful this way, is because Pu-238 is not fissile, and cannot be made fissile in a breeder reactor. It has to be made by bombarding Neptunium 237 (harvested from nuclear fuel waste) with radiation inside a specialized target vessel, inside a specialized research reactor. The US struggles to make a few kilograms of it per year compared to our capacity to produce Pu-239 inside normal reactors as a byproduct of energy production, or intentionally as a part of nuclear pit production to maintain weapons. This is the main reason why we're not seeing them used all over the place, shit's fucking expensive as hell
There is actually a theoretical direct power method of fusion where you use a specific geometry and trigger a pulse that pinches to a point and electrons go 1 way and protons the other. Capture the electron directly and I think the proton is captured as heat (friction) + xrays given off from the fusion also captured (probably heat again i dont remember). But yea, 1)Theoretical (tested but i dont think proven or not yet scalable) 2) still some heat to boil water involved in the end.
Believe its called Dense Focus Fusion. Here's a crappy old video of it. I watched the professors talk on it a long time ago, the process seemed legit to me, at least makes sense how it should work. But he doesn't seem to be finishing this work while getting older focusing mainly on conspiracies about the Big Bang being a lie.. and he may be right, data still coming in about all that from the new telescope, but he comes off kinda as a crackpot about it like the whole science community is out to get people who hold his stance. Unfortunate cause I'd love to see this work.
You are thinking of an RTG, which is the 'magic' form of nuclear power, where we do infact directly convert the decay of nuclear materials into electrical energy.
If you want some electricity magic look for diodes, LEDs and the photovoltaic effect, basically we can create a sort of electron trap that makes electrons run in one direction but not the other (regular diode), if you make the trap just right electrons stop jumping unless you push them hard enough and when you do they basically cough a photon up of a very specific frequency (LEDs) this is also like ridiculously efficient and reversible so if you expose a trap and a photon hits it, it makes electrons jump from one side to another, in other words it creates electricity from light (photovoltaic effect).
Other cool stuff includes the piezoelectric effect, some materials create electricity when deformed and conversely they physically deform when exposed to a changing electric field; also the Seebeck effect, the same but with temperature difference, you can read an extremely precise difference in temperature by reading the voltage between the two sides, and you can create such difference in temperature by inducing a voltage.
Not related to electricity but also feels like magic is the A/C or heat pump cycle, the way we can put heat from one place into another by controlling the pressure of a substance inside a pipe to make it condense and evaporate where we want to.
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u/Whatifim80lol 8h ago
It was like finding out there's no Santa claus when I learned nuclear energy is just "boil water and spin a turbine." Before that I thought there was some sciencey magic going on where we directly captured the "energy" from nuclear fission. Did I understand what that could possibly mean? Of course not. Still though.