Slashdot Mirror
Modeling the Economy As a Physics Problem
University of Utah physicist Tim Garrett has published a study that approaches the economy and its relation to global warming as a physics problem — and comes to some controversial conclusions: that rising carbon dioxide emissions cannot be stabilized unless the world's economy collapses or society builds the equivalent of one new nuclear power plant each day. The study was panned by economists and was rejected by several journals before its acceptance in the journal Climatic Change. "[Garrett discovered that] Throughout history, a simple physical constant... links global energy use to the world's accumulated economic productivity, adjusted for inflation. So it isn't necessary to consider population growth and standard of living in predicting society's future energy consumption and resulting carbon dioxide emissions. ... 'I'm not an economist, and I am approaching the economy as a physics problem,' Garrett says. 'I end up with a global economic growth model different than they have.' Garrett treats civilization like a 'heat engine' that 'consumes energy and does "work" in the form of economic production, which then spurs it to consume more energy,' he says. That constant is 9.7 (plus or minus 0.3) milliwatts per inflation-adjusted 1990 dollar. So if you look at economic and energy production at any specific time in history, 'each inflation-adjusted 1990 dollar would be supported by 9.7 milliwatts of primary energy consumption,' Garrett says. ... Perhaps the most provocative implication of Garrett's theory is that conserving energy doesn't reduce energy use, but spurs economic growth and more energy use."
This fits with an observation by insurance companies (or at least mine, USAA) that building safer cars results in people continuing to drive them to their preferred safety margin. We still end up with about as many crashes (but injuries are less).
While this is probably largely true, human demands do seem to expand to fill available resources, our demands aren't infinite.
The marginal value of your first dollar, or 10 dollars(depending on local cost of living), is enormous. You get to eat. The marginal value of your 1,000,001th dollar is a great deal smaller.
There isn't a fixed "ceiling" above which people demand no more energy; but there are a number of "floors" below which things get really ugly, really fast(like, "Rwandan Genocide" bad, not just "I want a cooler yacht" bad). If you can increase efficiency enough, it should be possible to reduce the amount of damage that needs to be done in order to head off genuinely bad outcomes.
There is also a second factor to consider: When people are desperate(or ignorant, or stupid), they will be willing to consume their capital to survive. Destroying fish stocks by catching juveniles, farming harder and harder until the topsoil erodes, polluting water supplies, eating the seed corn, deforestation to make charcoal(on the subject of deforestation, compare the Dominican Republic with Haiti. Same island, same location, one country has its forests, one doesn't. The Dominican Republic is merely poor. Haiti is deeply fucked.), and so forth. Even in strict economic terms(i.e. setting the intrinsic worth of "the environment", beyond its practical utility, at 0) this is a stupid plan. If the alternative is starving, though, people will do it anyway. If efficiency increases, fewer people will be desperate enough to eat their capital instead of their income.
Perhaps the most provocative implication of Garrett's theory is that conserving energy doesn't reduce energy use, but spurs economic growth and more energy use.
While I can't speak to the validity of the underlying theory as such, a conclusion like this doesn't really come as a shock. The 20th century saw an steady stream of "labor-saving" inventions that are now part of our daily lives, but we don't have more leisure time than our ancestors -- in many cases, we actually have less -- because all of that liberated time was promptly consumed by new forms of work.
Sooner or later, we're going to have to come to terms with our now obsolete species-wide obsession with material acquisition. It made sense before we developed tools and civilization: grab all you can while it's abundant because scarcity is the norm. Now that we have all we actually need and then some, we're just killing ourselves with the byproducts of our superfluous production.
Proud member of the Weirdo-American community.
This sounds like Jevons Paradox.
http://en.wikipedia.org/wiki/Jevons_paradox
When we conserve energy, we can and do use the saved energy for other activities. "conservation" is not really conservation if we promptly use the saved energy for another activity.
Consider the food supply. The population has now reached a size at which the current amount of food is not sufficient for everyone to eat well. So, scientists at ADM and other companies are trying to invent new ways to increase food production. Suppose that the scientists succeed and that we increase food production by 20%. The population, enjoying this additional food, now grows by an additonal 20%: we return to the original problem.
In the long run, the 4 horsemen will eventually impose their own solution on humankind. Many people will die in the process.
Inevitably, some Slashdotter will claim that yet-to-be discovered technology will always provide a fix for the problem. Believing that yet-to-be discovered technology will be discovered (and will be the salvation) is exactly equivalent to believing the numerous claims of religion. Often, the same Slashdotter who is atheist does not hestitate to believe in yet-to-be discovered technology. A hypocrite, a fool, or both?
Yeah, if an actual scientist had just come along and made the entire premise of my profession irrelevant, I'd be pretty hacked off too. You're taking it pretty well, actually, and yes, I will have fries with that.
If you were blocking sigs, you wouldn't have to read this.
I wouldn't worry about that, as the end result of *not* cutting back on energy use is also the eventual destruction of the world economy. We live unsustainably. Oil isn't forever. Nukes aren't forever. Enjoy it while it lasts.
The determined Real Programmer can write Fortran programs in any language.
Economists routinely use highly complicated mathematical models on stuff like this, and are just as routinely criticised for it because their simplifying assumptions aren't close enough to reality. Then along comes this bloke and uses a model that's not even based on human behaviour: the economy as a heat engine. No wonder he's been panned. Criticise economic models all you like, but at least the modern ones* have a foundation in human behaviour.
So economists are trying to figure things out from first principles, and having a rather difficult time because their necessary simplifying assumptions could possibly be simplifying away things that actually matter. While this guy seems to be looking at the economy as a black box, saying "it looks like this input and this output have always been related in the past, so what happens if they stay related in the future?". He's trying to come up with laws ("this is what happens") rather than theories ("this is why it happens"), and doesn't really need a foundation in human behavior. Much like we can know what gravity does, without actually having found a graviton or whatever current theories say we should find.
I'm glad I lived in the last century before the human race realized that it was going to die out because of the inbuilt greed of our genes which multiplied by our intelligence guarantee our extinction.
A common sentiment, shared by every generation since civilization began.
Indeed, reform of the way the economy is defined is needed. A collapse in "economic growth" need not necessarily lead to a drastic decrease in living standards. Vast amounts of energy are used in the world today to produce items with a lifetime far shorter than they could be. High quality engineering and craftsmanship could, at a slightly higher cost, produce items (furniture, cars, refrigerators, whatever) with lifetimes of many decades instead of a few years. Yeah, so there would be a lot less employment available as a result, both directly in manufacturing and indirectly in waste recycling, but people wouldn't need to buy as much either, so you could conceivably achieve shorter working hours and lessened energy/materials consumption (lessened economic activity) with little effect on people's quality of life. I'd even say it would be a better quality of life if everybody had to work less. The only way I could see to make something like that happen however would be massive regulation of manufacturing to prevent the production of garbage. I don't believe the problem with econmic activity is the use of resources, I think it is more a matter of how much we just waste. Leaving a light bulb turned on overnight is nothing compared to the amount of energy used to create all the plastic rubbish in landfills around the world.