4 ms·

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]
etskinner 3y ago
The sibling comment to this one helps clear this up: In short, they're not talking about the entire heat of the inner planet. They're talking about the rate at which heat that is transferred to the surface of the planet, not the thermal energy of the interior of the planet.
- jl6 3y ago
  ~180,000TWh of annual human energy production vs ~ 3,000,000,000,000,000TWh of thermal energy inside Earth.
- thriftwy 3y ago
  Power is not the same as energy obviously, but otherwise it is the rate at which the thermal energy is spent.
- mitthrowaway2 3y ago
  > the entire heat of the inner planet ... is an energy figure, not a power figure, unless you mean either the rate at which heat is added through thermal decay, or the rate at which heat is lost through conduction to the surface, both of which are at the same mid-ten-terrawatts order of magnitude as human power usage.
graypegg 3y ago
Over the many nuclear reactors, hydro stations, geothermal stations (which I guess is kind of cheating since it measures energy twice), tidal power stations, solar panels, wind turbines, gas and coal fired generators, and all the other odd-ball power generation devices used around the world, I could believe it. The heat can only get to a place where we actually measure it via lots of thermal mass that would slow things down. The energy emitted from the core of the earth, and human generated power combined is most likely dwarfed by the equivalent watts from sunlight alone. Assuming the low "realistic" estimate [0], the total amount of watts hitting the earth at any one time is 694.2 TW [1]... instantaneously. So that would add up much quicker. Edit: I'm an idiot, the sun doesn't face the whole earth at once. It would still be a lot at half that though! [0] https://en.wikipedia.org/wiki/Sunlight#Solar_constant https://en.wikipedia.org/wiki/Sunlight#Solar_constant [1] https://www.wolframalpha.com/input?i=%281.361+*+5.100644719%C3%9710%C2%B9%E2%81%B4%29Watts https://www.wolframalpha.com/input?i=%281.361+*+5.100644719%...
- lainga 3y ago
  Integrated over the course of a day, total disk solar irradiance for a rotating planet is 1/4 the solar constant. And in our specific planetary case, about 27% is reflected without reaching ground. So the effective whole-day whole-Earth "solar constant" at ground level is about (1362 W/m^2) * 0.25 * (1 - 0.27) ~= 250 W/m^2. https://en.wikipedia.org/wiki/Earth%27s_energy_budget#/media/File:Earth_heat_balance_Sankey_diagram.svg https://en.wikipedia.org/wiki/Earth%27s_energy_budget#/media...

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]

etskinner 3y ago

The sibling comment to this one helps clear this up: In short, they're not talking about the entire heat of the inner planet. They're talking about the rate at which heat that is transferred to the surface of the planet, not the thermal energy of the interior of the planet.

jl6 3y ago
~180,000TWh of annual human energy production vs ~ 3,000,000,000,000,000TWh of thermal energy inside Earth.
thriftwy 3y ago
Power is not the same as energy obviously, but otherwise it is the rate at which the thermal energy is spent.
mitthrowaway2 3y ago
> the entire heat of the inner planet ... is an energy figure, not a power figure, unless you mean either the rate at which heat is added through thermal decay, or the rate at which heat is lost through conduction to the surface, both of which are at the same mid-ten-terrawatts order of magnitude as human power usage.

graypegg 3y ago

Over the many nuclear reactors, hydro stations, geothermal stations (which I guess is kind of cheating since it measures energy twice), tidal power stations, solar panels, wind turbines, gas and coal fired generators, and all the other odd-ball power generation devices used around the world, I could believe it. The heat can only get to a place where we actually measure it via lots of thermal mass that would slow things down. The energy emitted from the core of the earth, and human generated power combined is most likely dwarfed by the equivalent watts from sunlight alone. Assuming the low "realistic" estimate [0], the total amount of watts hitting the earth at any one time is 694.2 TW [1]... instantaneously. So that would add up much quicker. Edit: I'm an idiot, the sun doesn't face the whole earth at once. It would still be a lot at half that though! [0] https://en.wikipedia.org/wiki/Sunlight#Solar_constant https://en.wikipedia.org/wiki/Sunlight#Solar_constant [1] https://www.wolframalpha.com/input?i=%281.361+*+5.100644719%C3%9710%C2%B9%E2%81%B4%29Watts https://www.wolframalpha.com/input?i=%281.361+*+5.100644719%...

lainga 3y ago
Integrated over the course of a day, total disk solar irradiance for a rotating planet is 1/4 the solar constant. And in our specific planetary case, about 27% is reflected without reaching ground. So the effective whole-day whole-Earth "solar constant" at ground level is about (1362 W/m^2) * 0.25 * (1 - 0.27) ~= 250 W/m^2. https://en.wikipedia.org/wiki/Earth%27s_energy_budget#/media/File:Earth_heat_balance_Sankey_diagram.svg https://en.wikipedia.org/wiki/Earth%27s_energy_budget#/media...