Imagine all the people - 80 billion people, all screwing with the planet
I updated my TF concept a bit, and got the numbers to be a bit more realistic (though not much less troubling).
By multiplying the average global TF figure by the world population, we can find the "Thermodynamic Population Equivalent" of the world over time. This value reflects both our increasing energy consumption and the growing world population. It is a measure of the increasing planetary impact of the growth in our technology, activity and numbers.
This calculation reveals the amount of damage that our technological activity is causing to the planet. This activity, driven by the energy we use in our daily lives, causes as much damage to the planetary systems we depend on as 80 billion people would if they were living in their raw human state, as hunter-gatherers.
There is potentially much more to be discovered here, but one thing jumps out at me immediately. TF seems like a very good proxy for the elusive "AT" term in the infamous I=PAT equation. By using it that way we can deduce that humanity today is having about 80 times the impact on the planet that we had 200 years ago.
We estimate that there were about 10 million people living on the planet just before the invention of agriculture between 5,000 and 8,000 years ago. Modern human civilization is today having about 8,000 times the impact on the planet as did our ancestors.
= new reply since forum marked as read
My "arrow of entropy ruins" typo was deliciously Freudian, I think 
The 1/5000 number came from being generous. it should have been 1/8000. Since the dawn of agriculture we have added over 4 trillion person-years of excess impact (aka damage) to the planet. To find out where I got this number, integrate the area under the red curve, and backcast it to a population of 10 million in 5,000 BCE - the last time humanity was truly sustainable.
The amount of damage done to the planet by human activity is truly incomprehensible. Especially if one rejects the analysis.
As a presumption.
I have a real problem with your claim that that was the last time human population was sustainable. That sounds like a pretty bold statement with a whole lot of hidden assumptions. Certainly agriculture has done a huge amount to increase productivity for the world's increasing population.
If you want to reject agriculture as a good idea, like my good friend, I am not going to be able to go along with that because we cannot go back to pre-agriculture days. Not with 8 billion people on the planet.
If you are arguing that it was a bad idea, well, maybe so. But it's too late for that, too.
The question is: What solutions do we have which are both practical and workable? How do we approach these problems short of destroying our civilization?
It's like I said to my friend, James, wringing ones hands about the evils of agriculture does not advance the dialog much if one does not have a credible path to achieve those goals.
Oh, and thanks for your replies. I find these discussions compelling, even when there's disagreement. We all learn from that.
Keep hope alive. Keep on stirring the pot, my friend.
It was simply what happened, regardless of what we feel about the consequences. From a thermodynamic perspective it was probably inevitable, as it enabled the next jump in system ordering on the planet.
From where I sit, it looks like we're caught in a trap. We of course can't go back. I've concluded that humanity literally cannot make a voluntary decision to climb back down the energy hill, because such a decision would go against the fundamental principles and driving forces of civilization. There are no practical, workable solutions in sight that will maintain human activity at its current level, let alone rate of growth, for more than a handful of years. We're drowning in our own waste, and climate change is about to bite us on the ass hard. We're having a very hard time finding enough high-density energy to keep the bus on the road, even if we accept the inevitable damage of climate change. Fracking is the symptom of this problem. Civilization's driving institutions - especially politics and economics - are showing disturbing signs of a lack of resilience. We're in very, very big trouble.
There is no way forward on this path, and there is no way back. We either need to redefine what "forward" means, in terms that don't require high-density energy throughput, or we will crash and burn within a couple of decades. Then we will go back down the energy hill, but we won't be walking down, we'll be tumbling.
Yeah, I intend to keep stirring the pot...
The direct contamination caused by the energy sources themselves is just one part of the overall impact that human energy use has on the environment.
Energy and population are intimately interlinked, but where you use the word "accommodate" I would use the word "enable". The reason there were never 7 billion hunter-gatherers is precisely because they didn't have the energy required to intensively exploit a relatively tiny patch of land per person for their survival. So they employed a myriad of techniques (including extensive infanticide) to keep the population pressure at bay. When high-density, high-quality exosomatic energy became widely available, that restriction was removed, and population exploded. Population growth was a direct result of energy exploitation. Look at what has happened to energy and population growth since 1850 or so.
The problem is, of course, not just population growth. Population is but one side of the population/consumption rectangle, whose area, aka Impact, is calculated in I=P*AT, where AT is per capita consumption. As resource availablity increases, that rectangle tends to expand until it consumes the available resources. At which point we figure out a way around or through the limit, and keep on growing. Like very, very, very smart cancer cells.
One of the presentations that, for me, made this point very clearly is this set of graphs from New Scientist in 2005:
I find it remarkable as well as educational that this idea can be so transparent to so many people, but is so opaque to others like you. I don't know if we'll be able to come to a meeting of the minds on this. Frankly our starting assumptions about what's going on in the world , as well as our values and beliefs, are so radically different that it makes convergence unlikely.
I've shown you conclusively there is no direct connection between energy and resource exploitation - it's possible to increase energy use while even decreasing impact on the environment - but you refuse to accept it.
You say impact "is" calculated using the equation I=P*AT. What units are you using to measure "impact"? Without units your equation is pseudo-scientific woo.
If you want to play the bandwagon card, I've honestly never encountered anyone who subscribes to your unique theory, or imagines as many causative links where none exist. For your collection:
...as to be simulated by the power consumption of a small city.
...and the rest of the solar system.