Crazy energy generating idea.

SSSnail

Lifer
Nov 29, 2006
17,458
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So, I was just thinking (I know right?), a desert is a pretty damn hot place (notice that I'm also a very observant, eh, observer). Take any deserts...

Now, if we place large metal tubes of some sort to collect that heat and channel it somewhere, preferably up, we can potentially drive turbines to create electricity.

Discuss.
 

Jeff7

Lifer
Jan 4, 2001
41,596
19
81
It's not really much of a thermal differential though - that's the key. You need a thermal differential to generate energy. The more thermal differential there is, the easier it is to extract energy. A difference between the desert and average global temperature really isn't all that much. Turbines and the like prefer temperature differentials of hundreds of degree, with pressurized steam as the fluid of choice. It's relatively easy to vaporize and condense, it's really cheap to obtain, and after it's been cooled sufficiently, it can be dumped out into a natural sink, such as a large lake or river.

Air also doesn't have much in the way of heat capacity per unit volume. A better way might be to have pipelines of water, heated in the desert, pumped elsewhere.
But there would be significant problems:
1) The pipeline would need to be VERY heavily insulated with some exceptional materials. Aerogel comes to mind. Insulating a large pipeline would probably cost trillions of dollars. Aerogel is really damn expensive. The other option is to user "superinsulators," which are evacuated barriers with multiple sheets of material suspended in them to minimize heat loss by radiation. Also very expensive.
2) Pumping the fluid would take a lot of energy, likely more than could be extracted from it.

Using geothermal thermal maintenance systems would be more effective. Those are the things where you drill into the ground, down to where the temperature remains fairly constant, around maybe 60°F year-round. That helps cool a building in the winter, and heat it in the winter, reducing the demand on a different heat source.

 

mugs

Lifer
Apr 29, 2003
48,920
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Yeah I don't know about that... but giant tanks of algae for biodiesel would probably work in a desert.
 

Jeff7

Lifer
Jan 4, 2001
41,596
19
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Originally posted by: mundane
Something like this?
Yes, this would work.

I interpreted to OP to mean something like just taking the latent heat of the desert and piping the warm air, or some other fluid, to somewhere that it could be used.

Solar collectors work though. :)
 

SSSnail

Lifer
Nov 29, 2006
17,458
83
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Well, I was thinking along the line of even less work than that. Now suppose the tubes area was large enough and was painted with heat attracting colors (black?), would there be enough of a temperature difference to channel the wind to drive turbines. Something extremely simple, think of a chimney.

Another idea would be to dig deep for water and use that for steam?
Originally posted by: AeroEngy
Do you mean like a Solar updraft tower Wiki Link

Damn it!!! :|
 

waffleironhead

Diamond Member
Aug 10, 2005
6,959
461
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Im still waiting for us to tap old faithful. I bet that predictable pressure surge could be used to make electricity. Ok maybe not old faithful but some of those other natural heat/steam sources. It is definitely a viable power source, just look at iceland.
 

SSSnail

Lifer
Nov 29, 2006
17,458
83
86
Originally posted by: waffleironhead
Im still waiting for us to tap old faithful. I bet that predictable pressure surge could be used to make electricity. Ok maybe not old faithful but some of those other natural heat/steam sources. It is definitely a viable power source, just look at iceland.
Or, heat pipes straight from volcanoes :p
 

Jeff7

Lifer
Jan 4, 2001
41,596
19
81
Originally posted by: SSSnail
Well, I was thinking along the line of even less work than that. Now suppose the tubes area was large enough and was painted with heat attracting colors (black?), would there be enough of a temperature difference to channel the wind to drive turbines. Something extremely simple, think of a chimney.
Those already exist, though not for driving turbines. They're used to heat water in homes, either for things like showering, or for heating the house.

That solar updraft tower looks nifty, though perhaps not exceedingly efficient.

I'd hesitate to use turbines except when necessary. Such a thing introduces efficiency losses.
If the heat can be used directly, that's much more efficient, such as with passive collectors for heating water, or geothermal heating systems.



 

Jugernot

Diamond Member
Oct 12, 1999
6,889
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It's called Geothermal energy.... it's been done for years and years.

It's very expensive.
 

aplefka

Lifer
Feb 29, 2004
12,014
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I don't understand how people aren't trying to use solar power. I mean sure it's expensive upfront but over the long run there's no way it's not cheaper, not to mention the technology/costs would improve if more people started using it.
 

thomsbrain

Lifer
Dec 4, 2001
18,148
1
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That's basically what most "solar" generators do. Most just use big arrays of mirrors to aim all the sunlight at one spot that gets really hot and drives fluid through a turbine. Arrays of photoelectric solar panels are pretty rare for single-purpose generating arrays that aren't retrofitted to buildings or something.
 

imported_Baloo

Golden Member
Feb 2, 2006
1,782
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Not a new idea. Solar water heaters are already in common use in arid/desert regions. In fact, Isreal requires Solar Waters heaters on all new construction/or when replacing existing water heating systems, Google solar water heaters; there are many to choose from. Oh, and the solar turbine, it's being done already: http://www.shpegs.com/
 

sao123

Lifer
May 27, 2002
12,651
203
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Originally posted by: SSSnail
So, I was just thinking (I know right?), a desert is a pretty damn hot place (notice that I'm also a very observant, eh, observer). Take any deserts...

Now, if we place large metal tubes of some sort to collect that heat and channel it somewhere, preferably up, we can potentially drive turbines to create electricity.

Discuss.

unfortunately even the hottest desert on earth is not hot enough to boil pressurized water in a pipe to pressurized steam. However, a modified idea on your design has been used in a few places... its called a CSP or Concentrated Solar Power, where mirrors and lenses are used to focus and magnify solar light so that it can heat pressurized water to a temperature hot enough that it can drive a turbine.