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Author Topic: Why is it impossible to harness Energy at 100% efficiency level?  (Read 2940 times)

Offline donchiragjain10036

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The total amount of energy in the Universe remains the same. It can only be transformed from one form to another. But, then , why can't it be transformed from one form to another with 100% efficiency ?


 

Offline Geezer

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That's a very good question!

I was hoping a real scientist would jump in and give you a proper answer, but as they all seem to be taking a sabbatical at the moment, I'll give it a shot.

It's a bit like taxes. As you probably know only too well, every time there is a transaction of some sort or another, the governing authorities try to grab a piece of the action. And they pass laws to make sure they get their share too. If you try to circumvent their laws, they get really stroppy and do nasty things like taking money out of your bank account, or even throwing you in the clink if they got really upset.

Our Universe (call it nature or whatever) is just like a Taxation Authority. Whenever you try to transform energy from one form to another (a transaction perhaps), it applies a tax. And, it has devised these really sneaky laws that make it impossible to avoid the tax. Apparently, there is no way to circumvent them.

The tax is "paid" in the form of heat energy, and its even got a name. It's called Entropy. Whenever you do anything, you increase the total amount of entropy in the Universe (no kidding).

Hopefully you are still breathing. If that is the case, you are increasing the total entropy of the Universe because you are converting various chemicals into other chemicals (in a sense you are burning them) and, in the process, your body in generating heat. That's the tax.

The energy in that heat will eventually dissipate into our Universe. It will warm up our Universe a tiny bit, but, as far as we know, ultimately there is no way that we can ever recover that energy in a form that will allow us to do something useful with it. We might delay the process by using the heat to power the atmosphere to power a wind turbine to etc., etc., but sooner or later, it goes back to the Universe.

Some current theories predict that, ultimately, our Universe will be nothing but heat. If that is true, entropy (the Tax Collector) takes all. I don't think we are too sure what he/she/it/them will do with it.
 

Offline maffsolo

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Can this apply to the energy transfer of an electric heater???
 

Offline Geezer

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Can this apply to the energy transfer of an electric heater???

Unfortunately, yes.

There had to be an irreversible conversion of energy at some point to produce the electricity. Ultimately, the heat that was produced by the electric heater will be given up to entropy.

I would not worry about it too much though. We're talking about timescales that are far beyond human comprehension.
 

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