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by shoo 2050 days ago
> I claim that economic growth cannot continue indefinitely. [...] the Earth has only one mechanism for releasing heat to space, and that’s via (infrared) radiation. We understand the phenomenon perfectly well, and can predict the surface temperature of the planet as a function of how much energy the human race produces. The upshot is that at a 2.3% growth rate (conveniently chosen to represent a 10× increase every century), we would reach boiling temperature in about 400 years. [Pained expression from economist.] And this statement is independent of technology. Even if we don’t have a name for the energy source yet, as long as it obeys thermodynamics, we cook ourselves with perpetual energy increase.

https://dothemath.ucsd.edu/2012/04/economist-meets-physicist...

5 comments

The physicist says that per capita energy use has surged, but that is only true in the developing world. California's per capita consumption of electrical energy has not changed since 1975. https://www.google.com/url?q=https://www.nrdc.org/sites/defa...
Consider that are dealing with a bias metric. California's weather makes it the least energy intensive state. In 1975 about 50% of the homes in my state had air-conditioning. Now its about 95%. Similar story with heating modern systems. Even in the 70s, older generations dealt with a much colder home in the winter than most people would normally allow today. The days that require climate control in my state are something like 2-3x the average number of days in California and at a much higher intensity.

Additionally, California has exported much of it's energy use to other states and countries.

We're talking about the growth rate of energy usage. California's weather has not changed since 1975 in a way that would reduce per capita energy usage.
I'm not talking about the weather changing. I'm talking about the growth of climate control using electricity in states that aren't California has led to continued energy demands.

Honestly your reply is frustrating because you sound like you don't understand my point. Please re read my comment from before.

Even in your scenario, we wouldn't expect per capita energy usage to increase faster than population growth (as the physicist claimed) because now everybody who wants climate control has it. The whole point is that per capita energy usage isn't growing exponentially in the developed world.
The point I made was regarding electricity usage in california from 1975 until now and how that comparison to the rest of the country isn't valid because it's a bias measure. In 1975 everyone who wanted climate control didn't have it, and that slowly changed to everyone being able to afford year round climate control. That drove huge growth in energy demands in most of the country. In that scenario we would certainly expect per capita energy usage to increase faster than population growth.

Your original claim about California doesn't hold because it's bias.

The decoupling argument breaks down when imports are considered.

"The material footprint of nations", Thomas O. Wiedmann, Heinz Schandl, Manfred Lenzen, Daniel Moran, Sangwon Suh, James West, and Keiichiro Kanemoto

PNAS first published September 3, 2013; https://doi.org/10.1073/pnas.1220362110

https://www.pnas.org/content/early/2013/08/28/1220362110

https://web.archive.org/web/20130906063246/https://newsroom....

That study shows zero growth in resource consumption instead of the negative growth observed without their methodology. This does not match the exponential growth in per capita consumption that the physicist assumes.
> First, Tom Murphy is confused by what economic growth is. You don't need increased energy consumption for economic growth.

> Economic growth measures the number of ways resources (material and non-material) are used hence resources are like the universe; "finite but unbounded." Tom Murphy is a typical Newtonian in his mindset and this imperial reasoning is so pre-Planck.

> Even in a so-called steady state any substitution from one material to another would seen as a kind of economic growth simply because markets the place more value on the newer item.

> Second. He assume that exponential economic growth is tied to some physical exponential. It is not. What is the basis for the recent exponential growth of physical consumption. It is growing population. It has been shown that energy growth of consumption doesn't increase much beyond 150k dollars. So once population stabilizes the physical growth model switches from exponential to linear. Tom Murphy never makes a linear growth model and thus his short-term peakerism.

http://mikenormaneconomics.blogspot.com/2012/04/tom-murphy-e...

The stock market has grown significantly while demand for energy has widely declined in the last five months. Every energy long bet has been a disaster.

Economic growth may not be able to continue indefinitely, it’s inconclusive, your computers can create more economic value with declining watts even if you can’t. However accounting value, which is what a stock market is, can definitely grow indefinitely.

> The stock market has grown significantly while demand for energy has widely declined in the last five months. Every energy long bet has been a disaster.

The stock market isn't backward looking, or even short term future looking. Note that someone only watching the S&P 500 would know that the coronavirus broke out in early March but probably think the situation had been completely resolved by August. We can't be sure what the stock market thinks it is seeing (or if it is right for that matter).

And if energy bets didn't turn out well, notice that that correlates to the US losing its position as the world's largest economy. China invested a bunch in energy and now have a noticeably bigger economy [0].

> Economic growth may not be able to continue indefinitely, it’s inconclusive, your computers can create more economic value with declining watts even if you can’t.

This growth isn't going to involve more people because they need food and isn't going to involve more stuff because that needs energy. It'll be a very abstract form of growth.

[0] https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)

The stock market is not the economy, and even how it is correlated to accounting reality is debatable.
Asset inflation is not economic growth.

(Though the two are very often confused.)

Stock markets occasionally move in directions other than up.

I made exactly that argument on HN a few months ago! I found that the inflection point would be 200-400 years into the future.
The economy is not limited to Earth.
Practically, it is.

Impractically, that buys you surprisingly little.

"Galactic-Scale Energy"

In 2450 years, we use as much as all hundred-billion stars in the Milky Way galaxy.

https://dothemath.ucsd.edu/2011/07/galactic-scale-energy/