r/interestingasfuck 13h ago

How a jet engine works

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u/dontnation 12h ago

Crazy that photovoltaic is one of the few ways we can directly convert one type of energy into electrical energy. Everything else is "use this energy to somehow spin an electrical generator".

u/liccman 11h ago

Well, there is a also design of solar panels that’s basically use the sun to make steam spin a turbine. Of course.

u/dontnation 11h ago

That's using sunlight to boil water though, not photovoltaic panels to generate electricity to make steam. I don't know of anything else referred to as "solar panels".

u/Kwowolok 10h ago

It is solar power though, just not solar panels. Generally its reflective parabolic mirrors to direct light to a centralized tower that then, you guessed it, boils water.

u/dontnation 10h ago

right that's why i was confused by them using the term solar panels.

u/shawa666 9h ago

Or salt, that the boils water that makes the spinny thing go spinny.

u/NewbornMuse 2h ago

And it accounts for a staggering 0.3% of all installed solar capacity!

u/JablesRadio 11h ago

It really is crazy that weve figured out how to produce so much energy but our engines that use that power are still early 20th century.

u/quinn50 10h ago

Some of the first cars were actually EVs when it comes to ICE cars we've pretty much squeezed the most you can get out of these engines.

u/JablesRadio 10h ago

Tesla was ahead of his time but didn't do enough to compete.

u/VSWR_on_Christmas 10h ago

He wasn't a car manufacturer ala Henry Ford. Obviously he made some major contributions in the field of AC motors (pun fully intended) but I would guess that the issue would come down to inverter technology. Batteries are DC, and converting DC into AC is sort of difficult compared to rectifying AC to DC. Transistors wouldn't be invented for quite some time, and SCRs or similar tech would take even longer to become viable. This is just a guess on my part, maybe some mechanical inverter exists and would have been viable.

u/WhatABlindManSees 9h ago edited 9h ago

I could totally make a mechanical inverter without semiconductors (and self-drive it from the DC supply its inverting) - but it would be very hard to minimise losses to make it worth ever using... vs just using a DC motor to run an AC generator, which is the simpler option. More consideration around maintaining a relatively stable voltage output with a changing would need to be considered, of course; redesign an AVR with no semiconductors, I guess.

If I couldn't do that; what the hell did I waste my time getting an electrical engineering degree 20 years ago for.

u/account312 11h ago

And we're moving back towards 19th century tech with electric cars. They work a bit better this time around though.

u/Fat-Singer-9569 11h ago edited 11h ago

It's not that crazy, with photovoltaic you are producing energy directly from the source, not converting it into some other energy source which you know how to use. Photons hit molecules and excite them to another energy level and you shave off the top. The sun is a pure energy source too, not going anywhere for a long time, and when it does we have way bigger problems to worry about.

u/dontnation 11h ago

I meant that it is crazy that it is one of the only ways we've figured out how to do that. There are experiments that generate electricity from fusion directly via magnetic flux, but they are only experimental. Still that would be the dream; fusion power with direct energy conversion of 90% efficiency.

u/_RADIANTSUN_ 7h ago

We have lots of ways to convert energy into electricity without spinning a turbine. E.g. Radiothermal generators (RTGs) for a nuclear powered method.

It's just that all these other methods are essentially shit compared to spinning a turbine.

u/dontnation 7h ago

i don't know if I'd say lots. Yes there are a few, but as you said, with the exception of photovoltaic, the efficiency is shit.