> The far more sensible way to view things when living in an infinite thermal bath of energy separated from absolute zero by a high value resistance is exergy defined as the available energy to do useful work.
We do not live in an infinite thermal bath of energy. It is, in fact, very very finite.
Exergy is based on the environment; Specifically, if you take some environment and bring the energy to equilibrium. This will be important in a bit, because you say a very dumb thing...
> Say the Carnot efficiency was maximized at 100C over room temperature of 300k, that would be 25% or 1-(300/400) because it penalizes you for the heat you got for free, the 300C
And there is the dumb thing.
You definitionally can not use any of the energy at 300C because that's your rejection temperature. You're not "using 100% of the heat energy you paid for" not only because you did not pay for the ambient heat, you have no mechanism in this scenario to move it to a lower temperature reservoir (and extract work from it) because it's already the lowest temperature in your system - by definition.
So yeah I guess "If you change the reality of the situation you can get different results" is technically true, but means nothing. You threw out the word 'exergy' (as if it was wholly unrelated to Carnot efficiency?!) and then quietly completely changed the parameters of the problem to do some bogus math. Exergy is about bringing a system's environment to equilibrium, and you tried to redefine the environment from a realistic and practical "Earth's surface" to a hypothetical "The entire universe."
> The earth has about 400k volts stored between its upper atmosphere and the ground where we live, with a net charge against true neutral of only a few volts making the surface voltage 200,000 or so. Your absolute electric car efficiency therefore goes from 200,800 volts to 200,000 volts never using the remaining potential to true neutrality.
For someone who claims to have a master's degree in mechanical engineering, I'd hope you'd have a better understanding that the Carnot Theorem only applies to heat engines and thermal gradients, not electromagnetic gradients.
Understanding that all voltages are relative, and that it makes no sense to use the average voltage between the ionosphere and the Earth's surface when evaluating anything other than discussing the voltage between the ionosphere and the Earths surface, is also something one should expect from someone with an advanced engineering degree.
> But thatâ(TM)s stupid because the current never flows to true neutral and canâ(TM)t flow to true neutral because of the giant resistor in the sky
It's stupid because even if it could flow from whatever the fuck "True neutral" is supposed to mean (midway point that is arbitrarily significant?), you're still dealing with a gradient that's tens of miles long but your car is only several feet high. Even if you created a conductive path to discharge the ionophere through your car, you'd still only get a fraction of a volt.
None of that is relevant here though, because you' don't use Carnot efficiency to describe something not operating with the flow of heat energy.
> So saying a thermodynamic process is effectively described in absolute terms by Carnot is just as silly as saying electric cars are less than 1% efficient.
Well no, because Carnot efficiency is a well established principle of thermodynamics - a direct consequence of the second law - that actually works in both theory and practice, and the electric car thing is some delusional bullshit you came up with. Big difference.
=Smidge=
