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Because I can never pass up a chance to mention it, the fiery core of the Earth that's moving those plates around is an approximately 45 terawatt engine; human

Because I can never pass up a chance to mention it, the fiery core of the Earth that's moving those plates around is an approximately 45 terawatt engine; human civilization is currently around 19 terawatts. Obviously we're not going to devote our entire economy to producing a mineral, and we're talking about millions of years versus decades, but it's still crazy to me that humans and the Earth itself operate on the same energy-scale.

redblacktree 3y ago
That's fascinating. Thank you for sharing. That really puts the scale of human activity into context.
Arrath 3y ago
> the fiery core of the Earth that's moving those plates around is an approximately 45 terawatt engine; human civilization is currently around 19 terawatts Oh wow that is mind blowing! I would have thought we were at a smaller proportion, to be honest.
- saalweachter 3y ago
  If you want to feel small again, on the other end of things, 173,000 terawatts of sunlight hits the Earth. Earth's biosphere uses something like 1% of that (depending on your definition of "used", but whatever), so we have Earth's biosphere at something like 1700 terawatts, dwarfing both us and Earth's fiery core.
  - teslabox 3y ago
    The energy of sunlight that hits the ocean is absorbed, and flows into the deep ocean. A smaller percentage of the energy that hits land is absorbed, but this rapidly radiated away at night.
    - saalweachter 3y ago
      Ok, one last one: global warming is basically that energy imbalance: the Earth is currently absorbing, on average, more energy from the sun than it radiates back, for a variety of reasons (change in atmospheric composition, change in surface reflectivity). That energy imbalance amounts to 500 TW.
bilsbie 3y ago
I’m skeptical we create a level of power near 50% of the entire heat of the inner planet.
- philipkglass 3y ago
  Surprisingly, it is true: https://en.wikipedia.org/wiki/Geothermal_energy#Resources https://en.wikipedia.org/wiki/Geothermal_energy#Resources The Earth's internal thermal energy flows to the surface by conduction at a rate of 44.2 terawatts (TW) [21], and is replenished by radioactive decay of minerals at a rate of 30 TW. [22] [21] https://agupubs.onlinelibrary.wiley.com/doi/10.1029/93RG01249 https://agupubs.onlinelibrary.wiley.com/doi/10.1029/93RG0124... [22] https://web.archive.org/web/20120217184740/http://geoheat.oit.edu/bulletin/bull28-3/art2.pdf https://web.archive.org/web/20120217184740/http://geoheat.oi...
  - ajmurmann 3y ago
    The parent said "power near 50% of the entire heat of the inner planet.". What you are describing sounds like the leaked power from the inner planet. These sound very different to me. One statement is about power the other about energy sitting there
    - Turskarama 3y ago
      Given that heat is a store of _energy_ rather than power, I don't think there's another reasonable interpretation of the _power_ of the core other than the amount that leaks.
    - hughesjj 3y ago
      I mean as far as production is concerned radioactive decay is the only energy source. The rest is latent heat and friction+tidal forces. The earth has been cooling and slowing rotation every since the theia impact.
      - deleted 3y ago
        [deleted]
thriftwy 3y ago
Obviously, only a very tiny proportion of that power is spent towards making the clays that we needed. We could spend a fraction of what we have and still outdo Earth by orders of magnitude.
- saalweachter 3y ago
  Yeah, but we're also talking about out-doing it by about six orders of magnitude, to produce millions of years of production by the Earth in mere years by man. So I'm not sure which one I'd bet on.
beAbU 3y ago
Is the 49TW the total amount of energy the earth radiates from the core? I'm struggling to reason about this. The core is a hot mass of matter, that's slowly cooling down. There is no energy "produced" here, no? So where does the 49TW go? Edit: my questions got answered by someone posting a wikipedia link elsewhere: https://en.wikipedia.org/wiki/Geothermal_energy#Resources https://en.wikipedia.org/wiki/Geothermal_energy#Resources Seems energy is being produced by means of radioactive decay.

redblacktree 3y ago

That's fascinating. Thank you for sharing. That really puts the scale of human activity into context.

Arrath 3y ago

> the fiery core of the Earth that's moving those plates around is an approximately 45 terawatt engine; human civilization is currently around 19 terawatts Oh wow that is mind blowing! I would have thought we were at a smaller proportion, to be honest.

saalweachter 3y ago
If you want to feel small again, on the other end of things, 173,000 terawatts of sunlight hits the Earth. Earth's biosphere uses something like 1% of that (depending on your definition of "used", but whatever), so we have Earth's biosphere at something like 1700 terawatts, dwarfing both us and Earth's fiery core.
- teslabox 3y ago
  The energy of sunlight that hits the ocean is absorbed, and flows into the deep ocean. A smaller percentage of the energy that hits land is absorbed, but this rapidly radiated away at night.
  - saalweachter 3y ago
    Ok, one last one: global warming is basically that energy imbalance: the Earth is currently absorbing, on average, more energy from the sun than it radiates back, for a variety of reasons (change in atmospheric composition, change in surface reflectivity). That energy imbalance amounts to 500 TW.

bilsbie 3y ago

I’m skeptical we create a level of power near 50% of the entire heat of the inner planet.

philipkglass 3y ago
Surprisingly, it is true: https://en.wikipedia.org/wiki/Geothermal_energy#Resources https://en.wikipedia.org/wiki/Geothermal_energy#Resources The Earth's internal thermal energy flows to the surface by conduction at a rate of 44.2 terawatts (TW) [21], and is replenished by radioactive decay of minerals at a rate of 30 TW. [22] [21] https://agupubs.onlinelibrary.wiley.com/doi/10.1029/93RG01249 https://agupubs.onlinelibrary.wiley.com/doi/10.1029/93RG0124... [22] https://web.archive.org/web/20120217184740/http://geoheat.oit.edu/bulletin/bull28-3/art2.pdf https://web.archive.org/web/20120217184740/http://geoheat.oi...
- ajmurmann 3y ago
  The parent said "power near 50% of the entire heat of the inner planet.". What you are describing sounds like the leaked power from the inner planet. These sound very different to me. One statement is about power the other about energy sitting there
  - Turskarama 3y ago
    Given that heat is a store of _energy_ rather than power, I don't think there's another reasonable interpretation of the _power_ of the core other than the amount that leaks.
  - hughesjj 3y ago
    I mean as far as production is concerned radioactive decay is the only energy source. The rest is latent heat and friction+tidal forces. The earth has been cooling and slowing rotation every since the theia impact.
    - deleted 3y ago
      [deleted]

thriftwy 3y ago

Obviously, only a very tiny proportion of that power is spent towards making the clays that we needed. We could spend a fraction of what we have and still outdo Earth by orders of magnitude.

saalweachter 3y ago
Yeah, but we're also talking about out-doing it by about six orders of magnitude, to produce millions of years of production by the Earth in mere years by man. So I'm not sure which one I'd bet on.

beAbU 3y ago

Is the 49TW the total amount of energy the earth radiates from the core? I'm struggling to reason about this. The core is a hot mass of matter, that's slowly cooling down. There is no energy "produced" here, no? So where does the 49TW go? Edit: my questions got answered by someone posting a wikipedia link elsewhere: https://en.wikipedia.org/wiki/Geothermal_energy#Resources https://en.wikipedia.org/wiki/Geothermal_energy#Resources Seems energy is being produced by means of radioactive decay.