5 ms·

I wonder how many wats of power we would be able to generate before earth slows down for i.e. 1 second longer day.

by npodbielski 2y ago

IshKebab 2y ago
That's easy to work out but I can tell you not it's going to be more than we will ever use.
- barbazoo 2y ago
  Typical human response
- Beijinger 2y ago
  You have no idea, what amount of energy we will be able to use the long run.
  - ada1981 2y ago
    220, 221, whatever it takes.
- janpot 2y ago
  "640K ought to be enough for anybody"
- tiagod 2y ago
  We have potentially millions or billions of years of history in front of us. If we find a way and a motive to have self-sustaining communities outside this planet, and considering our own history, it looks at least plausible that we will continue spreading, after dominating an entire planet against the brutal odds of natural selection, which we basically hacked with our consciousness to reach this state. Keep in mind that energy is not electricity. When a rocket is burning huge amounts of fuel to reach orbit, that's energy we're using, a lot of it.
af78 2y ago
I'm taking figures from https://en.wikipedia.org/wiki/Rotational_energy https://en.wikipedia.org/wiki/Rotational_energy Moment of inertia of the Earth: I=8.04e37 Angular velocity, with sidereal rotation period of 23.93 hours: ω0=2π/(23.93 × 3600) Angular velocity, with sidereal rotation period of 23.93 hours plus one second: ω1=2π/(23.93 × 3600 + 1) Rotational energy difference: .5 × I × ω0 ** 2 - .5 × I × ω1 ** 2 ≈ 4.96e+24 J For comparison, according to https://ourworldindata.org/energy-production-consumption https://ourworldindata.org/energy-production-consumption the total amount of energy consumed on Earth in 2023 was 180E3 TWh i.e. 6.48e+20 J Slowing down the Earth by one second would be equivalent to 7661 times this amount.
adalacelove 2y ago
According to Wikipedia [1] we consume 9717 Mtoe or equivalently 408 TJ (per year, although it is not explictely stated, which I find annoying). The earth moment of inertia is about I=8e37 kg m2 [2] The energy extracted by a slowdown of angular speed from wa to wb would be 1/2 I(wa2-wb2). Approx wa=2pi/86400 and wb=2pi/86401. Energy extracted: 4.9e24J=4.9e12TJ. We would have energy for about 12 billion years. If I double check with Kagi's assistant with Claude 3.7 (I'm in my phone and I could easily have made an error) it starts with my exact reasoning and figures but messes up final numbers (so close!!!) to give a total of 40 billion years, which nevertheless is the correct order of magnitude. [1] https://en.m.wikipedia.org/wiki/World_energy_supply_and_consumption https://en.m.wikipedia.org/wiki/World_energy_supply_and_cons... [2] https://scienceworld.wolfram.com/physics/MomentofInertiaEarth.html https://scienceworld.wolfram.com/physics/MomentofInertiaEart...
mmooss 2y ago
https://news.ycombinator.com/item?id=43526555 https://news.ycombinator.com/item?id=43526555

I wonder how many wats of power we would be able to generate before earth slows down for i.e. 1 second longer day.

IshKebab 2y ago

That's easy to work out but I can tell you not it's going to be more than we will ever use.

barbazoo 2y ago
Typical human response
Beijinger 2y ago
You have no idea, what amount of energy we will be able to use the long run.
- ada1981 2y ago
  220, 221, whatever it takes.
janpot 2y ago
"640K ought to be enough for anybody"
tiagod 2y ago
We have potentially millions or billions of years of history in front of us. If we find a way and a motive to have self-sustaining communities outside this planet, and considering our own history, it looks at least plausible that we will continue spreading, after dominating an entire planet against the brutal odds of natural selection, which we basically hacked with our consciousness to reach this state. Keep in mind that energy is not electricity. When a rocket is burning huge amounts of fuel to reach orbit, that's energy we're using, a lot of it.

af78 2y ago

I'm taking figures from https://en.wikipedia.org/wiki/Rotational_energy https://en.wikipedia.org/wiki/Rotational_energy Moment of inertia of the Earth: I=8.04e37 Angular velocity, with sidereal rotation period of 23.93 hours: ω0=2π/(23.93 × 3600) Angular velocity, with sidereal rotation period of 23.93 hours plus one second: ω1=2π/(23.93 × 3600 + 1) Rotational energy difference: .5 × I × ω0 ** 2 - .5 × I × ω1 ** 2 ≈ 4.96e+24 J For comparison, according to https://ourworldindata.org/energy-production-consumption https://ourworldindata.org/energy-production-consumption the total amount of energy consumed on Earth in 2023 was 180E3 TWh i.e. 6.48e+20 J Slowing down the Earth by one second would be equivalent to 7661 times this amount.

adalacelove 2y ago

According to Wikipedia [1] we consume 9717 Mtoe or equivalently 408 TJ (per year, although it is not explictely stated, which I find annoying). The earth moment of inertia is about I=8e37 kg m2 [2] The energy extracted by a slowdown of angular speed from wa to wb would be 1/2 I(wa2-wb2). Approx wa=2pi/86400 and wb=2pi/86401. Energy extracted: 4.9e24J=4.9e12TJ. We would have energy for about 12 billion years. If I double check with Kagi's assistant with Claude 3.7 (I'm in my phone and I could easily have made an error) it starts with my exact reasoning and figures but messes up final numbers (so close!!!) to give a total of 40 billion years, which nevertheless is the correct order of magnitude. [1] https://en.m.wikipedia.org/wiki/World_energy_supply_and_consumption https://en.m.wikipedia.org/wiki/World_energy_supply_and_cons... [2] https://scienceworld.wolfram.com/physics/MomentofInertiaEarth.html https://scienceworld.wolfram.com/physics/MomentofInertiaEart...

mmooss 2y ago

https://news.ycombinator.com/item?id=43526555 https://news.ycombinator.com/item?id=43526555