Well, let's work it out. Your scenario of mankind dissipating through cheap nuclear processes 10,000 times more heat than their current energy use 10^18 J/day would mean doubling roughly the Earth's present 10^22 J/day radiated power (almost 100% solar presently).
Black body radiated power P goes as T to the power 4 (cf e.g.http://en.wikipedia.org/wiki/Black_body ) so T goes as P to the power 1/4. Therefore if P is doubled, T is multiplied by 2^(1/4) = 1.2, which takes us from our present ~300K to ~360K. That's a 60°C global warming if I am not mistaken. If a means to eliminate excess heat more efficiently than passive radiation is not found then unlimited power generation will be very dangerous indeed! Michel ----- Original Message ----- From: "Harry Veeder" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Friday, January 12, 2007 8:14 AM Subject: Re: [Vo]: FRE > Jed Rothwell wrote: > >> Harry Veeder wrote: >> >>> Heat production may be trivial today, but that may change in the future. >> >> It is not trivial today. It is already a problem. I do not think it >> will become as bad a problem as Paul predicts, even with cold fusion. >> >> >>> After all humanity now produces 10,000 times more heat than it did centuries >>> ago. Is it not possible that in the centuries to come, humanity might be >>> producing 10,000 times more heat than today? >> >> We covered this topic here several times, and I covered it in the >> book. I recommend that energy intense manufacturing be conducted off >> planet in the distant future. Products should be brought to earth via >> a network of space elevators, and shipped via relatively slow (low >> energy, subsonic) transport. >> >> - Jed > > > Ok. The salient point of this discussion is that even if humanity > NEVER produced green house gases, it is reasonable to assume, all other > things being equal, that if heat production becomes large enough the average > global temperature would indeed rise. > > Harry >
