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Comment by aurareturn | Hacker News Reader

  This felt false to me, LED bulbs are generally 10x more efficient, so the average number of lights would have had to increase 10 fold, and this is ignoring the savings from not having AC cool those other 50 watts a bulb that went to heat.

Jevons Paradox does not state that there is a 1:1 relationship between efficiency increase and consumption. A 2x increase in efficiency does not always result in a 2x increase in consumption.

With that said, it would not surprise me if there is a 10x increase in light sources (not total lumens) since LEDs.

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Yes, I don't have 10x more lightbulbs but now household appliance has an LED. I just installed new GFCI outlets and all of them have LEDs too!

The comparison becomes meaningless when we count the milliwatt, sub-Lumen LED in an outlet wirh incandescents. "I had 8 incandescent lightbulbs, but now have 1000s of LEDs- including outlets, TV backlights, DVR status" isn't comparing like with like.

Yeah probably a meaningless comparison for Jevons Paradox (and its application to NVDA) since that is about resource use and LEDs are not a resource

Jevons Paradox describes the situation where a 10x efficiency increase results in a >10x deployment of lumens, such that the amount of energy consumed for lightning increases relative to when lighting was inefficient.

Which has happened historically.

  Comparing this with the solid blue price line showing price indicates that the 100 fold fall in price per unit of light in the 20th century was due to increased efficiency, mainly as electricity replaced gas.  Yet demand rose strongly over the period, increasing more than 100 fold.  This challenges the view that increases in efficiency translate into reductions in demand, and thus emissions.

https://onclimatechangepolicydotorg.wordpress.com/low-carbon...

That's a good source, although that historical analysis extends to the year 2000 when even CFLs only had reached ~30% market share, and well before LED lighting hit mass adoption. It is only speculating about LEDs. There's no question that lighting demand has continued to grow but the efficiency increase has also been remarkable, so unless you know of another source that does the math, it's unclear to me to what extent it's ended up balancing out in this case.

Another confounder to Jevons' paradox is that the price of the input (electricity) can also change, independent of changes in efficiency. If electricity prices were to go up ten-fold during the switch to LED lighting, then we wouldn't expect much change in illumination (probably a net decrease, as people would be hurting so much from other electricity expenditures that they'd be hunting for any savings on their energy bill). That's of course a fictional scenario, but in the case of GPUs, well, they have been getting quite expensive.

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