5 ms·

Wiki says it's basically nil: > The flow of heat from Earth's interior to the surface is estimated at 47±2 terawatts And > Despite its geological significanc

Wiki says it's basically nil: > The flow of heat from Earth's interior to the surface is estimated at 47±2 terawatts And > Despite its geological significance, Earth's interior heat contributes only 0.03% of Earth's total energy budget at the surface, which is dominated by 173,000 TW of incoming solar radiation https://en.wikipedia.org/wiki/Earth%27s_internal_heat_budget https://en.wikipedia.org/wiki/Earth%27s_internal_heat_budget

donatj 4y ago
Thank you so much for the link, there is a lot in here that is genuinely fascinating! For instance heat from the surface “thus penetrates only several tens of centimeters on the daily cycle and only several tens of meters on the annual cycle”
- ZeroGravitas 4y ago
  This is why ground source heat pumps are suprisingly effective. You're drawing on the yearly solar inflow to the ground, at a depth where the temperature is quite stable, due to accumulating and averaging over years.
  - DLTADragonHawk 4y ago
    My curiosity in using things like heat pumps is that what happens when you move too much of that heat energy away. The heat might be doing nothing but, it has been there for a long time. At what point is too much heat displaced to the surface and what is the outcome of that?
    - ZeroGravitas 4y ago
      For them to actually work the energy needs to be replaced, flowing from the hot areas to the (relatively) cold areas, mostly coming from the sun. If you have a small area and continually pump the heat out then you end up with the inside of a freezer, which uses the same tech for exactly that purpose, but also intentionally insulates to prevent the heat getting back in.
    - antisthenes 4y ago
      You can read about what happened to the London underground over the years. Except the process has been sort of reversed: there was heat being introduced into the deep layers of clay and rock. https://en.wikipedia.org/wiki/London_Underground_cooling https://en.wikipedia.org/wiki/London_Underground_cooling

donatj 4y ago

Thank you so much for the link, there is a lot in here that is genuinely fascinating! For instance heat from the surface “thus penetrates only several tens of centimeters on the daily cycle and only several tens of meters on the annual cycle”

ZeroGravitas 4y ago
This is why ground source heat pumps are suprisingly effective. You're drawing on the yearly solar inflow to the ground, at a depth where the temperature is quite stable, due to accumulating and averaging over years.
- DLTADragonHawk 4y ago
  My curiosity in using things like heat pumps is that what happens when you move too much of that heat energy away. The heat might be doing nothing but, it has been there for a long time. At what point is too much heat displaced to the surface and what is the outcome of that?
  - ZeroGravitas 4y ago
    For them to actually work the energy needs to be replaced, flowing from the hot areas to the (relatively) cold areas, mostly coming from the sun. If you have a small area and continually pump the heat out then you end up with the inside of a freezer, which uses the same tech for exactly that purpose, but also intentionally insulates to prevent the heat getting back in.
  - antisthenes 4y ago
    You can read about what happened to the London underground over the years. Except the process has been sort of reversed: there was heat being introduced into the deep layers of clay and rock. https://en.wikipedia.org/wiki/London_Underground_cooling https://en.wikipedia.org/wiki/London_Underground_cooling