This is mainly because I need info for my sci fi universe.
Even when we have a way of producing electricity and powering vehicles which doesn't involve spewing crap into the atmosphere, we'll still be making the world a hotter place. Does anyone know how much energy we would have to produce to effect a significant change in global temperatures, compared to what we produce now?.
A question of heat
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speaker-to-trolls
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A question of heat
Post Number 1066 achieved Sun Feb 22, 2009 3:19 pm(board time, 8:19GMT)
Batman: What do these guys want anyway?
Superman: Take over the world... Or rob banks, I'm not sure.
Batman: What do these guys want anyway?
Superman: Take over the world... Or rob banks, I'm not sure.
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Wicked Pilot
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Re: A question of heat
The amount of heat we humans would produce would pale in comparison to what we get from the sun on a continous basis.speaker-to-trolls wrote:Does anyone know how much energy we would have to produce to effect a significant change in global temperatures, compared to what we produce now?.
The most basic assumption about the world is that it does not contradict itself.
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Kuroneko
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The complete answer to this depends on the planet, and is impossible to answer without a detailed model of the planet's climate. In short, this is the kind of question one would use supercomputers for. In this case, you are ignoring greenhouse gases, which makes it a bit easier, but there will still be some change in the weather, which may alter critical parameters like the Earth's albedo (clouds or lack of them, but also urbanization, etc.), especially if the power generation is not uniform throughout the planet (which it won't be). In any case, a back-of-the-envelope calculation that assumes constancy of all other parameters is actually quite easy, so you can just use that.
The Earth's blackbody termperature is T = 254.3K with albedo of a = 0.306 [1], making the the emissive power σεT^4 = 165W/m², where ε = 1-a = 0.694. With a surface area of A = 5.1006e14m², this makes the total emission to be P = 8.39e16W. In comparison, if the radiation temperature was raised 1K, the figure would have been 8.53e16W, which is a difference of about 1e15W. That's not all that much for sci-fi universes, although it is still about some orders of magnitude away from the current power generation capabilities. It should also be noted that the radiation temperature is not the same thing as the thermodynamic temperature (in Earth's case, a difference of almost 34K), but one can still use that as a guide to how severe the changes will be with this hypoethetical superclean method of power generation.
The Earth's blackbody termperature is T = 254.3K with albedo of a = 0.306 [1], making the the emissive power σεT^4 = 165W/m², where ε = 1-a = 0.694. With a surface area of A = 5.1006e14m², this makes the total emission to be P = 8.39e16W. In comparison, if the radiation temperature was raised 1K, the figure would have been 8.53e16W, which is a difference of about 1e15W. That's not all that much for sci-fi universes, although it is still about some orders of magnitude away from the current power generation capabilities. It should also be noted that the radiation temperature is not the same thing as the thermodynamic temperature (in Earth's case, a difference of almost 34K), but one can still use that as a guide to how severe the changes will be with this hypoethetical superclean method of power generation.