Are there any examples of a system using geothermal + solar heating to induce electrical currents with a Peltier heater?

In an area with a large amount of sun (Colorado for instance) we have enough radiant heat to last us all year, even through winter. So with heat from the sun all year, and cooling from the earth, why can't we make a geosolar electric generator with few to no moving parts and maintenance?

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On that topic, is there any information on using heat gradient to move water within the system, instead of relying on mechanized pumps?

Like a big ass sterling engine-ish/single loop thingy. (Sorry if i'm getting too technical. :D)

Truly thinking outside the box.

Interesting.

Cost and efficiency are the problems.

And I was wondering if the difference in temperature between a radiant heated slab, and the air temp above it would be sufficient to power a sterling type engine - don't they work on relatively close temp differentials?

With a very limited efficiency. But in an array the mechanism is there. With sterling, focused solar radiation is probably more efficient than a peltier.

Again, jon's right about the cost, but the concept is there.

Cost is therefore an issue of evolving the industry. I don't like the words "can't" and "won't"...they're not very helpful for the thinkers. Useful for the do-ers, surely.

Better Peltier gallium arsenide junctions used as a heat pump or AC are only 5 to 7% the efficiency of a vapor compression or sterling cycle. In use as you envision, the semiconductor cost per watt is many times higher than PV junction cost, hence putting a thermal collector on the backof PV is much more effective and lower cost, which is why you do not see any seeback effect devices on roofs.

Peltiers have been used for generation used with 'nuclear pigs' for long term deep space exploration devices

Seebeck, perhaps?

Thanks for the info. Makes sense. Never heard of the Nuclear Pigs, but from what I can infer, it's a clever idea. I'll have to read up on that. Again, thanks.

Seebeck, perhaps?

You are correct, gotta give the profs something to correct (grin)

This month's ASHRAE mag had an article about solid state cooling - there has been some progress, but it seems it'll be awhile before these replace vapor compression in apps needing much more than a couple hundred Btuh