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Hot Asteroid Power

Orbit asteroids around the sun and back to Earth, then use the heat
  (+4, -7)
(+4, -7)
  [vote for,

To harvest the Sun's energy more efficiently, launch an asteroid on an orbit that will take it around the far side of the Sun and then back to Earth, since closer to the sun means more light per area (a powerful thruster beyond current technology would be needed). When the glowing molten rock returns to Earth orbit, collect the heat with a geothermal system and send it back to Earth, or just let it glow in orbit to light one side of the Earth, eliminating the need for streetlights.

When fusion and magic are invented, halfbakers will already know how to use them.

sninctown, Mar 31 2006

Comet energy transport (HB) Comet_20Energy_20Transport
Convert on-board. Previously on the HB (> 2yrs) [sophocles, Apr 01 2006]

Mercury http://en.wikipedia...ki/Mercury_(planet)
A close orbiting astroid like body that doesnt hold heat [jhomrighaus, Apr 04 2006]


       Only problem here is that space is a VERY cold place. The time required for the Astroid to return to our orbit would be very large and in that time all the heat gained would have been radiated off into space long before returning to earth's orbit.   

       I believe that this approach will not work.
jhomrighaus, Mar 31 2006

       It would be less impractical if you did something chemical to store the energy, or maybe just used the heat to refine the asteroid. But it would still be the hard way to do solar energy collection. -
baconbrain, Mar 31 2006

       [snictown] Ignore the fools and their fishbones.   

       You can convert the energy on-board in numerous ways if you worry about thermal losses in a vacuum (radiative is the only loss as there is no conduction or convection.)   

       The only thing preventing me from bunning it is that I posted the same/similar thing here (I think better of course), back in November '03. [link]
sophocles, Apr 01 2006

       [jhomrighaus], heat radiating into space? I always thought that heat was movement of particles. How does that radiate exactly?
zeno, Apr 04 2006

       [zeno] it's called black body radiation, and is the third method of heat transfer. first is conduction: hot (fast) particles bouncing into each other. Second is convection (which doesn't work in zero-g) which is hot particles forming currents due to pressure differential. Radiation is simple: every particle, body etc has a temperature, and therefore (it's a big therefore, I know: go read a thermodynamics or physics textbook...) radiates electromagnetic energy proportional to it's temperarture to the fourth power. So the hotter a particle is, the more radiation. So a difference in temperature results in a difference in radiative intensity between two bodies. Space has a "background radiation temperature", I forget the term they use, of something like 50k (kelvin). So anything in space will radiate away it's excess heat until it reaches the equilibrium of 50k (or whatever it is). This method of heat transfer works great in a vacuum. 0bviously this equilibrium temperature is different near the sun...   

       Oh, and the actual mechanism for the radiation is the charge difference between an energetic (read hot) electron and a nucleus. electron drops down to a lower energy level, gives off radiation. the rate at which they drop down (and how much potential they drop by) is dependent on temperature.   

       clear as mud?   

       google "radiative heat transfer" or "black body radiation" hope this helps.
Custardguts, Apr 04 2006

       //0bviously this equilibrium temperature is different near the sun...//   

       Actually the eq temperature is the same every where in space where there is a hard vacuum, be it a mile from the sun or deep space. What is different is the amount of energy being imparted upon an object by its proximity to a strong source of radiation(in this case the sun).   

       On the planet Mercury the temperature swings from 90K(-280F, -175C) to more than 700K(620F, 330C). This is a perfect example of why this idea is not feasible. With no atmosphere to insulate it mercury's surface temperature cycles more than 600K from day to night(about 58 days) This is also why astronauts and space craft require extensive insulation and heating capabilites otherwise they would freeze VERY quickly.   

       Also a note on particles carrying heat. Heat transfer is not a physical process but rather an energy transfer process as was eluded to. In the case of physical heat transfer it is simply energy being passed from the stationary object to the moving object.
jhomrighaus, Apr 04 2006

       So, all you boners: Are you really thinking that we couldn't convert that heat/radiative energy from the sun to something more storable, like say H2, before we got too far from the sun?
sophocles, Apr 04 2006

       Wow, thanks that was a good explanation.
zeno, Apr 05 2006


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