Ive been testing combustion engines made of wood but keep getting more energy out than I put in...
this post was submitted on 18 Dec 2023
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Lisa, in this meme we obey the laws of thermodynamics!
Sorry, I’m a bit dumb for this one.
Could someone please explain?
There's no such thing as a 100% efficient "engine". But in this case, since the waste heat is put to use (heating the house), OP thinks there's a loophole.
But, house would also need to be soundproof. Any noise leaking to the outside is lost energy.
Ah, but that’s by design: it also acts as a soothing white noise machine.
Then you might point out the exhaust and all it’s associated wastes, but that’s by design: it produces a heady and aromatic product for recreational huffing.
Then you might point out the vibrations, but that’s by design: the engine also provides invigorating massages to relax taut muscles.
You. Come sell my book
Let's allow a rounding error for 99.51% shall we?
Don't tell anyone, but I actually only used 1 significant figure, so anything above 50% will do.
I'm also using the version of significant figures where I work backwards from the answer, otherwise I'd need 95% or higher and that's too difficult.
Most engines are less than 30% efficient at producing movement. The majority of the energy is lost as heat.
Thermodynamics tells us that pretty much all energy ends up as heat. In a closed system, any device that uses energy is 100% efficient at making heat. A 1000W computer will make exactly as much heat as a 1000W heater.
A 100% efficient engine can only exist if the desired output is heat, thus making it a pretty useless engine. Also, in a closed system, the exhaust cannot leave.
A 1000W computer will make exactly as much heat as a 1000W heater.
All space heaters should be coin miners (or some other borderline useless energy wasting tech, like AI training). Change my mind.
We have enough of a chip shortage, tyvm
If you want to be philanthropic, there are programs you can run that use your computer's idle time to process data for cancer research and such.
You can sign up for research crunching.
Furnace.
But even a furnace/fireplace is subject to incomplete combustion, where some portion of the wood is transformed into byproducts that rob some of the energy of the fire. There's actually a big difference in the amount of energy you can get out of a fire, depending on the type of stove that's used.
That's some of what NGOs have tried to do for developing countries - find cheap and easily produceabke stove designs that can reduce the amount of wood needed and improve air quality in the home.
Yes he is incorrect. NG furnace is 95% efficient iirc.
Wait till you hear about reverse cyxling air conditioning it exceeds 100% efficiency.
I'm more impressed by that fact that if either runs perfectly silent or that your house has perfect sound insulation
I have a spherical frictionless house in a vacuum.
In this economy?
At these prices?
this is true only if you dont vent the exhaust outside making the air inside quite fun to breathe
He burns h2
so a heater and a humidifier all in one, now just have to make sure that it doesnt eat all the oxygen or make it rain inside
He doesn't burn very well.
Fyi I think they're around 95%.
It's only 100% efficient if you're also letting all the exhaust into the house too...