Carnot's theorem means that the fraction Tcold/Thot of the energy wasn't convertible into useful work to begin with. It doesn't "dissipate" in that it is inevitable that it will flow out of the system into the "cold sink". I understand "dissipation" as entropy producion inside the system, not across its boundaries. In that sense, x - Tcold/Thot does dissipate, and 1 - x is converted into work.
x flows into the cold sink. Of this, Tcold/Thot flows into the cold sink inevitably, and the rest (x - Tcold/Thot) as a result of not being captured in the bulk. That is definitely wasted.
Now, the remaining 1 - x can either be dissipated in the bulk or captured as "useful work".
Back in the ecological analogy, 1 - x is made up of the energy dissipated by the weather system, and the energy used by the biosphere, of which we're taking an ever large share. When the capital development of a country becomes a by-product of the activities of a casino, the job is likely to be ill-done. — John M. Keynes
I am inclined to see now that some local waste is inevitable. To sort the mess, even a colder sink would be needed (say, the outer space). What does it imply for global warming by the greenhouse effect? Are we not letting infrared photons (as "waste" from high energy Sun photons) to escape the earth, and so we have to suffer "unexportable" entropy increase throughout all planet's systems?
The fraction 1 - Tcold/Thot is the "high-quality energy" that we can let dissipate, be captured by the ecosphere, or use ourselves.
Some local waste is inevitable, but that's more in the nature of an engineering problem if you like. There's no reason in principle why very close to 100% of 1 - Tcold/Thot cannot be tapped. That's what a Type-1 civilisation does.
As for lowering the cold temperature, if we decided to run large industrial facilities in space they could run at low temperatures and reduce the Tcold. Note that the Earth is warmer than it would be if it had no atmosphere: we already have a substantial greenhouse effect making the Earth habitable and keeping Tcold relatively high. When the capital development of a country becomes a by-product of the activities of a casino, the job is likely to be ill-done. — John M. Keynes
What do you mean with "Some local waste is inevitable..."? Do you mean here that the minimal portion Tcold/Twarm of energy will go to 'warm' the cold sink? That in principle reduces its quality other things being neutral, however minutely, right? Or do you mean that ideally we could actually have no waste, in whatever sense?
It is the part that could be captured but isn't that is wasted (i.e., if more than Tc/Th flows out to the cold sink, the excess can properly be described as wasted - some of this waste will indeed occur because of local dissipation). The part that is not wasted may or may not be exploited "usefully".
My main focus is not whether energy is used most effectively, but how much 'waste' has to be dumped locally. In many texts on complex systems, including on self-organized criticality, I read that dissipation waste is a characteristic feature of complex systems. So I wonder, how necessary is this feature.
Once again, my philosophy here is that the spontaneous arrangement of a stationary flow does no work and dissipates all the energy that could usefully be captured as work. Self-organisation of the complex system arises when the flow is fast enough as to trigger a period-doubling cascade (the stationary flow becomes unstable at the point of the first bifurcation). Then some of the energy is used to drive the (quasi)periodic limit cycle (self-organisation), that is, to do work against local dissipation (inside the system) and less flows out directly. When the capital development of a country becomes a by-product of the activities of a casino, the job is likely to be ill-done. — John M. Keynes
