Jevons Paradox • Hacker News Board

Re: Jevons Paradox

#41

Post by pygy_ » Sun, Feb 25, 2018, 5:15 PM UTC

darkmighty wrote: post #26

pygy_ wrote: post #19

Earlier quoted context omitted.

Renewable energy has an environmental cost as well. The solar and wind energy that isn't currently used by humans is dissipated by atmospheric, marine, geological and biological processes. It is a zero-sum game, and increasing our consumption will disrupt other processes.

> It is a zero-sum game, and increasing our consumption will disrupt other processes. You need to define what you mean by "being a zero-sum game". For example, in terms of entropy (which is a possible metric in the context of "dissipation") it isn't a zero-sum game -- certain processes increase entropy more, some less. In terms of total instantaneous thermal absorption, which defines the temperature of the Earth, it…

The sun output and the earth surface are constant, that's the zero sum resources I was talking about.

> Putting solar cells in barren deserts isn't going to disrupt local lifeforms simply because there aren't any.

No, but it will cool down the places, which will affect winds patterns and rainfall, which can in turn affect life forms at a distance. I suppose you could paint the ground around the pannels black, and carefully chose the panel/reflector density to have a neutral thermal effect.

Re: Jevons Paradox

#42

Post by omgwtfbyobbq » Sun, Feb 25, 2018, 6:48 PM UTC

spodek wrote: post #40

omgwtfbyobbq wrote: post #39

Earlier quoted context omitted.

The authors of that paper are estimating that energy use for lighting will eventually reach past levels because of the rebound effect and population growth, not Jevon's paradox. Jevon's paradox occurs when an increase in efficiency results in so much additional use that per capita energy consumption increases. If the average car is made twice as efficient and that leads to it being driven three times it's annual mile…

> Jevon's paradox occurs when an increase in efficiency results in so much additional use that per capita energy consumption increases. They also describe that we are lighting things we didn't use to light, keeping the lights on longer ( not just households but decorative building lights, decorative bridge lights, etc), and other per capita increases. The quote above states per capita increases clearly: > "It's not j…

Per-capita light use does increase. In order for Jevon's paradox to apply, per capita energy use would have to increase more than the decrease from improved efficiency. So if LEDs are ten times more efficient, per capita light use would have to increase by 10+ times for Jevon's to apply.

Putting it another way, Jevon's is just an example of the rebound effect where more energy is used after the efficiency improvement than before. It can happen, but it's not very common.

If people were to switch to LEDs and their energy consumption dropped to a tenth of what it was, they could triple the number of lights in their house, leave those lights on 24/7/365 (as opposed to for 8 hours a day), and still be using less energy than with incandescents. That's the rebound effect. If they quadruple the number of lights and triple the time those lights are on, they would use more energy than they did before the switch to LEDs. That's Jevon's paradox.

Re: Jevons Paradox

#43

Post by omgwtfbyobbq » Sun, Feb 25, 2018, 7:11 PM UTC

danieltillett wrote: post #7

roenxi wrote: post #4

Applying this paradox in reverse (which is paraphrasing the wiki article) - if introducing energy efficiency measures causes energy use to go down then someone needs to ask probing questions about what is going on. Increased efficiency should be linked, all else equal, to increased use of a resource.

Introducing energy efficiency measures does cause usage to go down in the short term, but assuming demand is elastic, then it will go up over time as people consume more. Where Jevons Paradox has most utility is showing the futility of unilateral individual action. Don't think you are doing anything to help the environment by turning off that light switch.

Turning off a light switch isn't futile, it's just not optimal. What you're describing can happen, but isn't common. In that situation, someone using less decreases price such that someone else uses more to the point where price recovers.

https://en.wikipedia.org/wiki/Price_elasticity_of_demand#Eff...

In the real world, efficiency increases aren't perfect, and we do use something more if it's efficient, but the vast majority of the time, the efficiency increase still reduces usage. It's usually not a maximal reduction because of the redbound effect (except for some appliances), but in every recent case, overall emergy use does drop.

https://www.everycrsreport.com/files/20010730_RS20981_bebfb5...

Re: Jevons Paradox

#44

Post by pmcg » Sat, Mar 03, 2018, 6:19 PM UTC

kingofhdds wrote: post #28

To the best of my knowledge, coal consumption reduced eventually, and exactly technology apparently did play some role.

Coal consumption increased steadily since 1865 and is almost at its all time high right now. There was a tiny dip in the last few years, but oil consumption is still increasing.

Re: Jevons Paradox

#45

Post by pmcg » Sat, Mar 03, 2018, 6:28 PM UTC

woodandsteel wrote: post #37

So, if, for instance, the price of energy dropped to zero, people's consumption of it would become infinite. And ditto for anything else that people use. For some reason I find that rather improbable.

I don't think this applies to division by zero.

But I expect that in general, for most things humans consume, as efficiency has increased, consumption has increased too.

Re: Jevons Paradox

#46

Post by Isinlor » Sun, Mar 04, 2018, 8:06 PM UTC

srtjstjsj wrote: post #35

roenxi wrote: post #13

Earlier quoted context omitted.

Actually, Jeveron's paradox would hold in the case you mentioned. Someone who gave you heated water would give it to you with an implicit quota otherwise a rational actor use an infinite amount of it. If I actually had free no-holds-barred heated water, I'd run a pipe down to the local laundry and sell it at a profit. That is the rational response - the reason you don't see people doing that is because nobody offers…

If hot water were free, you couldn't sell it. There is a point at which people don't need more water; they aren't Singularity-minded water maximizers.

In communist countries, hot water was sort of free i.e. the cost was shared. People were having open windows during winter in order to have fresh air and heating in order to have warmth, also heating outside as a by-product :) . Hot water usage went drastically down in building where capitalist rules were introduced and water meters were installed per flat.