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0 pointsjvanderbot1y ago0 comments

> It takes more energy to produce more stuff

Energy consumption is also about using that stuff. And in rich countries like the USA, a lot of energy goes to using things or just moving people. So it's possible to build more and use less energy, even if you don't reduce the energy cost of building things. They can simply become more efficient to use and move.

In USA, 30% is just homes and commercial sector. 40% is transportation. 30% is "industry". By a sort-of inverse-amdahl's law, it's possible to get lower energy use with more throughput even if we don't make "industry" more efficient.

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pfdietz1y ago

I will note that the minimum energy needed to move people, as dictated by the laws of physics, is zero. There is no net change in average gravitational potential energy per capita, and any energy that goes into kinetic energy can in principle be recovered with arbitrarily high efficiency.

There are losses in practice, of course, to friction, air resistance, etc. but the laws of physics don't impose any lower bound on these.

macspoofing1y ago

>So it's possible to build more and use less energy, even if you don't reduce the energy cost of building things.

In principle I can imagine that being true - but that's not represented in our world, so it is an open question if you can 'build more and use less energy' in the real world.

rtkwe1y ago

It's really really not, you can see it in the data. I took GDP per capita and kg oil equivalent energy consumption per capita and in 1970 the very year the article highlights as us falling off the HA curve and representing 'lost' GDP the exact opposite happens. We begin producing way more GDP per capita using the same unit of energy.

It's basically a piece wise function if you graph it. 1960 to 1970 the GPD/energy unit ratio is largely stable then after that it begins increasing monotonically going from .69 to 7.94.

https://news.ycombinator.com/item?id=41392222

ForHackernews1y ago

It's represented everywhere that efficiency counts. I haven't fact-checked it, but one source[0] claims that refinements in the design of soda cans (thinner walls, different shapes) since 1960 saves "at least 90 million kilograms of aluminum annually."

[0] https://www.youtube.com/watch?v=hUhisi2FBuw

toss11y ago

Exactly!! There a uncountable millions of examples, and you're right, anywhere efficiency counts, which is pretty much everywhere.

jvanderbotOP1y ago

It's also irrelevant as anything other than a limiting case. The issue is with the statement that energy use must go up to produce more GDP or that not increasing energy use means we cannot raise GDP or even that GDP is limited by a flat energy use.

USA GDP is still on basically the same exponential curve, yet energy is flat. That's the counter example. The rest is exposition.

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