by yesplease » Tue 04 Dec 2007, 19:51:11
$this->bbcode_second_pass_quote('Ludi', 'T')he median of estimates Monte cites is actually 2- 5 billion.
http://www.ilea.org/leaf/richard2002.htmlIn my opinion, as safe carrying capacity would probably be 3 billion or less, but we have to work with the numbers we have (short of actively killing billions of people).
Thanks for the link, it's very interesting! It seems that all the lower estimates tend to be based on energy and current standards of living, which IMO is downright silly. The way we're going, I wonder if we could even support a few hundred thousand under current standards given that we haven't been this close to midnight on the doomsday clock since the collapse of the USSR.
That being said, most of our current energy use, and by proxy the conclusions that come from assumptions regarding this, is flawed. By that I mean it's deliberately inflated because we are at a point where we could be harnessing a significant number of new energy streams for different applications in a fairly short time span. Those who control/own the initial energy streams needed to take appropriate measures to insure we use as much of their product for as long as possible. Currently, we deliberate induce inefficiency to increase levels of consumption and lock out alternatives. In some cases, this is easy to deal with, like replacing incandescents with CFLs and/or LEDs where directed lighting is needed, which would cut power consumption associated with home lighting into a
quarter to fifth of what it was.
Inefficiency wrt personal transportation was easy to pull off, since most personal transportation that could accommodate more than one person had been by way of horse and carriage. In this case, a large vehicle with a lot (from a human perspective) of power was needed for transportation of more than one person and stuff. By pushing power, convenience, and seating requirements up, oil companies could pump out way more oil, which meant more money initially, a faster peak, and more money from that, while minimizing the amount of oil that was left in the ground, and essentially worthless after we transition to other energy sources. Auto dealers love this because high power requirements mean complex vehicles, so repairs and turn around are relatively high.
That being said, the average vehicle now uses ~2200Wh/mile in the states, but the minimum needed to do what that vehicle does 90+% of the time, transport one person and minimal cargo, is ~5Wh/mile. We're using ~440 times more energy than we need to move an individual and small amount of cargo. Now, that's the extreme, but there are plenty of vehicle designs that aren't as spartan, w/ climate control and alla that, which could reduce energy use for personal transportation by an order of magnitude.
The only thing people get out of large vehicles for personal transportation is a large vehicle for personal transportation. The downsides are, more income spent on personal transportation, reduced lifespan due to pollution and a lack of exercise, problems with mental health associated with body image, etc... All this is so that small groups can accrue disproportionate amounts of wealth and control larger groups through this, which has been pretty consistent throughout human history. Do we need all the externalities associated with excess consumption in order to support our existing social hierarchies? Probably not. Will we continue on the same path we have been on? Maybe. But, we don't have to.
Anyway, to summarize, any estimates on carrying capacity due to energy are suspect because energy use is purposefully inflated. Food production otoh, while still wasteful and destructive imo, doesn't waste orders of magnitude more than it produces, and can provide a reasonable approximation of human carrying capacity as opposed to energy/lifestyle based estimates. Driving two ton barges in air so polluted it's the equivalent of smoking a pack a day, while getting next to no exercise, and dying early, w/ all that emotional an physical baggage along the way, is not a lifestyle I would wish on anyone. And it's definitely not something we should attempt to sustain.

$this->bbcode_second_pass_quote('Professor Membrane', ' ')Not now son, I'm making ... TOAST!