The solar updraft tower
 

http://en.wikipedia.org/wiki/Solar_updraft_tower
http://upload.wikimedia.org/wikipedi..._tower.svg.png

It's a big tower surrounded by glass. The air under the glass gets heated by the sun and goes up trough the tower spinning the generators
This technology is very simple, almost perfect I say, one such tower could work for hundreds of years if maintained

Australia plans to build one with a collection area of 7km in diameter.
Spain built one with an area of 244 m diameter, it worked for 8 years and generated some 50kW at it's maximum, until it was closed due to "structural problems"

I would like to see these towers wherever there is space for them, their simplicity is inspiring

I think it's a pretty neat method and seems to have a lot of potential to be commercialized. I bet they'll eventually figure out how to replace the glass with a flexible membrane that would make construction and operation somewhat simpler and cheaper.

Anyplace there is a decent temperature difference can be utilized to make power, such as oceanic temp differences between deep water and surface water, using either direct turbine drives like you show above, or a heat engine that really lights my fire are the Sterling cycle engines http://en.wikipedia.org/wiki/Stirling_cycle

There is beauty in designs like that. It really is radically simple, yet at the same time wonderfully functional. I was watching the Lord of the Rings the other day and started wondering about the benefits of living in burrows as they did in the fictional Shire. Ever wonder how many simple, yet wonderfully innovative ideas we're overlooking out of habit? Why do we have to get energy from burning coal? Why do we have to live in wood and sheetrock homes? Are there better alternatives?

Well yeah, I mean of course. This solar tower is one fantastic example.

Edit: here is another example:
http://www.geekologie.com/2007/12/ai...with_the_p.php
An air purifier that is just a plant.

This is the problem. In the space of 244m you generated about 5* what a standard emergency generator did.

Edit: Hosed my math and I'm no longer at home with the numbers, but it would take a crapload of these working as 100% efficiency to power a Western nation.

Its cool, I like it, I could see where it might have uses, but its not a solution to anything but perhaps some local issues in this form. Concepts for these are fantastic, in the science fiction 'fantastic' sense. They would be the tallest structures ever built by man, cover miles and miles of land, and only be really usable in certain climates.

Mild thread jack for Willravel. Check out
www.ourcoolhouse.com/final.htm

There are many other designs available as well.

Pai mai I agree the simplicity of this design is inspiring also.

The wiki article estimates costs around 25-35 cents/kWh. That is pretty close to current alt energy methods. Screw it, just build a few nuke plants.