Exponential Economist Meets Finite Physicist (2012)

is the sun uniform heat? how do ectothermic animals and plants using photosynthesis work? I'm not sure why you think you can magically break thermodynamic symmetry...

it's powered by a heat differential, you are draining the heat from the system and storing it or dissipating it under motion - reducing the overall flux - over time by cooling the hot side and heating the cool side eventually some equilibrium is reached, depending on how efficient the throughput is and how much heat you have, you then exhaust your temperature gradient and need to move somewhere hotter or colder.

one of us is very confused here. i claim "you can reduce heat locally in the earth system", and give examples: capturing and insulating it (trees, plants), converting it into other types of energy (genetically modified sea sponge/robots), as well as venting it into space through an atmospheric/orbital seebeck ring.

im not breaking any laws of thermodynamics, i am turning the planet into a refrigerator.

edit: to clarify i am claiming it's possible to move heat away from the habitable thin boundary layer by conversion: storage, mechanical use or venting.

Reducing the temperature gradient(s) of the system does not reduce the amount of heat in the system. When the temperature gradient decreases, that just means that there isn’t as much variation in the temperatures in the system. The temperatures become more uniform. When the temperatures are uniform, you cannot use the temperature in order to do useful work.

.. I now notice that I missed that you mentioned putting things into orbit?

I misunderstood and thought you meant putting the seebeck stuff in the ocean, as if that would cool down the oceans.

Yeah, if you pump heat into places that you can remove from earth, or have emit black body radiation more effectively, that would help.

But, Unless you are ejecting stuff away from earth, there is still a max rate you can radiate away heat at a given temperature? Oh, but, hm, if you made your thing in orbit really really hot, hm.

Is that what you were saying?

Sorry for misunderstanding what you meant about the ocean.

Not sure what you mean by storing heat.

You could store energy obtained from (the smoothing-out of) a temperature gradient, but that isn’t storing the heat, just the energy extracted as the temperature gradient goes away. It doesn’t decrease the amount of heat?

And I suppose if you have some endothermic reaction (like melting ice) you can decrease the amount of heat around, (and then if you freeze it again, you release the heat), which is sort of like storing heat, but it isn’t like you can store arbitrarily large amounts of heat this way. You would need arbitrarily large amounts of stuff to have react.

I’m still fairly sure you cannot “transform heat into kinetic or chemical energy”, but rather, you can transform a difference in temperatures, and a potential for heat to be exchanged, into kinetic or chemical or whatever energy?

In the example of that mechanism for converting a temperature gradient into electricity, suppose you had two regions with particular and different initial temperatures , which are in contact with opposite sides of the mechanism. The two regions have the same mass and are made of the same material. How do you expect the temperature of all the parts after reaching equilibrium to depend on the initial temperature? I expect that the total heat will remain the same (even though you did extract some energy as the difference in temperatures went away).

Also, pumping heat around costs energy. To move things against the tendency for temperatures to equalize, costs energy, right?

I don’t understand why the fact that earth is not homogeneous would be a reason to not call it a system?

I don’t see how the specifics of geology and such are relevant here. The question is: under what circumstances can we keep the part of a system that we care about to stay at a low temperature while waste heat is being added to the system at an arbitrarily fast rate, and the only way we have for heat to leave the system is blackbody radiation? (Assuming the system is connected/contiguous and stuff)

Now it sounds like you are suggesting that we just make the inside of the earth hotter while keeping our part cool?

Energy usage per point of GDP = f(t)

Then we can obviously construct a hypothetical scenario:

lim t->inf g(t) * f(t) = C

This is obviously possible if one flips it over, making economic growth depend on the rate of which we reduce the energy cost for producing a dollar of GDP.

This obviously means that production must be decoupled from the sheer AMOUNT of physical goods, as those are necessarily limited.

To increase GDP, we do not need to increase the amount we produce but the value of what we produce.

Sure, one way to increase GDP would be to produce two cars for the same resource use as one car would need. And that has limits.

But if I can produce a rocket that can propel something to orbit with the resource use of a car, I’m am not only enabling more rockets being built, but also actively reduce the energy cost of one.