You still haven't explained an energy source which can do the job. If not solar, what?
I guess we could beam it in from space mirrors, but then you have heating issues.
I've spent the past hour doing math on this, it's about two pages...and well beyond the tedium of what I could reasonably expect you to read. If you're willing to just accept my conclusions rather than expect me to reasonably format a legible explanation of how they were derived, we get the following end result:
1) The US is notoriously inefficient and is a poor choice of model for a futuristic society. Let's use Japan as a model instead of the US. It's more modern, yet nevertheless consumes half as much energy per person
2) Previously provided numbers appear to be off by a factor of about 4. I get:
Earth receives:
8,646,597,720,000,000 gigajoules per year from the sun
The energy consumption of 7 trillion people living a Japanese lifestyle rather than a US/derived/assumed lifestye:
1,187,900,000,000,000 gigajoules per year
That's 13% of what earth receives from the sun. Not the 50% or 100% that were proposed earlier. I realize there's a great deal of room for error in this kind of thing. Converting joules and watts and scientific notion to long form, the significance of rounding off at one point being exacerbated after multiplying by millions and billions later...etc. If anybody can provide a more reliable estimate that doesn't involve me spending more hours examining the question, I'm willing to look at it. But...these were the figures I came up with based on available data, making what I considered to be fairly reasonable assumptions, and the final result was considerably larger than I expected.
If you're willing to accept that figure, we can proceed from there to figure out how to generate that much energy. I think it can be done.
I mentioned ONE thing about severe poverty in Manila as an aside, since you brought up Manila as a great example of high-density living, and you keep misconstruing it as a main argument point. Let's drop that.
Ok. Dropping population density as a problem.
The point about cities destroying the environment is that 1000 times the current population would entail covering the entire world's non-ocean with 1 big city, or at least converting the entire surface to solely meet our needs. Bye bye to all existing eco systems.
...again...why is this a problem? I agree that if you build a city over a natural environment, you lose the natural envirorment. But I don't see that as a good argument against building cities.
Or is this a purely aesthetic consideration?
O2 => CO2
Scale of the problemAccording to your own numbers, nature produces 25 much times as much carbon dioxide as human civiliztion does. A 1000 times increase in human population, assuming current levels of CO2 output, would result in a net of increase of 40 times the current "natural" output.
However:
http://micpohling.wordpress.com/2007/03/27/math-how-much-co2-is-emitted-by-human-on-earth-annually/Between 91% and 94% of that CO2 production caused by humans is produced by the use of fossil fuels. So...stop burning fossil fuels. No more coal. Use electric cars. Use solar/wind/geothermal/nuclear/etc. energy sources. Simply using different technologies than the ones we happen to be using now, and our CO2 emmissions can be reduced by roughly a factor of ten.
So...instead of a 40x increase in net Co2 production with 7 trillion people we have have a 4x increase with 7 trillion people. At this point it would be easy to cheat. 7 trillion was an arbitrary choice for simplicity of math. My original claim was "trillions." I never specified how many trillions. The specific figure of 7 trillion came as a result of your statement in
this post about multiping current population by 1000.
If we say 2 trillion instead of 7, that 4x increase becomes a 1.14x increase. Just more than double current levels. Not that big of a deal. Easily within our ability to absorb.
However...if we do decide to stick with the 7 trillion figure, a 4x increase in CO2 output is still easily within reason to suggest that we could accommodate it.
1) It's not necessarily even an issue. Obviously the human race didn't die off from carbon dioxide poisoning when we went from
1 billion to 7 billion people. Nor did it die off from carbon dioxide poisoning when we started producing ten times as much due to industrialization. The natural system has already demonstrated a large ability to adapt. At present, I think we lack any data to show us how much increase there would have to be before it created any major problems. It's possible the system could absorb a 4x increase without any direct intervention from us at all.
2) Plants (and algae especially) metabolize carbon dioxide. If you do need less CO2, then simply grow more of them.
Now, I can already hear you eagerly getting excited at the chance to shoot this down because of lack of space. After all, we're building a city everywhere. But this was already
addressed here:
"...there are three dimensions for us to work with. There's a LOT of available space if you simply go up or down. And incidentally there's nothing stopping us from using that vertical space for things other than storing people. You can grow food in the z-axis and build parks and pools and anything else you want up there too. There's no reason to build exclusively at surface level."3) http://en.wikipedia.org/wiki/Algae_bioreactorhttp://www.youtube.com/watch?v=yWBBJgKkqjIGive them CO2. It makes them happy and they give us oxygen.
4) Your 7 trillion figure assumed only using the available land. That leaves the remaining 70.8% of the earth's
water surface area...and incidentally quite a lot of volume. Good place for algae.