Solar Wind Downdraft Tower

[Ksheed]

Interesting concept, coming to a desert near you.

http://www.gizmag.com/solar-wind-energy-downdraft-tower/32607/

[Chimera]

Interesting concept, coming to a desert near you.

http://www.gizmag.com/solar-wind-energy-downdraft-tower/32607/

Interesting . . . until we see how much water we'll have to pipe to it and determine where the water will come from.  I can hear LA and Vegas screaming now.  I wonder if the increase in humidity will have an impact on the local ecology.

[Marlin]

  I saw this a number of years ago in Scientific American one of the side benefits is that it cleans particulates out of the air. It does need a water source but then Palo Verde solved that problem for it's cooling towers.

[cypher89]

From the SWP in California which also pumps large amounts of water over a high lift of 2000 ft it consumes 3000 kwh per acre foot of water.  Pretty hard to image this idea would even be self sustaining from a net power prospective.

[HydroDave63]

From the SWP in California which also pumps large amounts of water over a high lift of 2000 ft it consumes 3000 kwh per acre foot of water.  Pretty hard to image this idea would even be self sustaining from a net power prospective.

Exactly right! This is another one of these bridge-to-nowhere techy ideas, right up there with the carbon nanofiber Space Elevator, Skylon ramjet airliners flying Mach 10 at edge of space, and cargo train tunnel from China-under-Bering-Sea-to-US ideas that would be somewhere between impractical and downright dangerous if attempted.

[peteshonkwiler]

If this technology works as well as described, I'm wondering if nukes are looking at retrofits of their cooling towers to incorporate it. Be one heck of a Green PR move.

[Marlin]

If this technology works as well as described, I'm wondering if nukes are looking at retrofits of their cooling towers to incorporate it. Be one heck of a Green PR move.

I doubt the cooling spray would overcome the waste heat from a 1000 MW reactor.

[GLW]

This is not new, this is a better tech paper than the infomercial at the beginning of the thread:

http://www.climatetechwiki.org/technology/energy_tower

from 2001:

http://www.transnational-renewables.org/Gregor_Czisch/projekte/new_et-brochure_zaslavsky.pdf

the big issue is return on the investment,...

deserts with large populations of well paid citizens which can afford commercial power rates in close proximity to the producing towers are a limited scenario on the world stage,...

for Israel, one of the significant drawbacks was security,...

towers 3000 feet tall and over a hundred feet in diameter are just too big a target for people who like to blow things up to make a statement,...

same problem for us (USA), the big one envisioned for Arizona will be right on the border with Mexico,...

arguably one of the most porous borders in the Western Hemisphere,...

imagine spending 300 million dollars to build a spectacular monument to clean energy only to have a bunch of psychotics across the Mexican border zero in on it from 3 plus miles away with surplus mortars from the USSR pounding your huge electricity making pipedream into a shamble of rubbled wreckage,...

all this as the bought off Federales take their sweet time getting to the scene of the perpetrators only to report the perps escaped into who knows where (probably with kids in tow, to north of the border, seeking humanitarian asylum),...

I'm just saying, these are very real concerns, the best places for these machines quite often do not have populations with enough disposable income to afford the monthly bill or, they are not in the most secure of locales for such a huge soft target,...

Maybe Saudi Arabia, Qatar, Iran and places of that ilk,...

Morocco, Israel, Iraq, Libya or within 20 miles of the US-Mexico border!?!?!?

not so much,....  

[peteshonkwiler]

I doubt the cooling spray would overcome the waste heat from a 1000 MW reactor.

That would be a volume vs. time design challenge, wouldn't it?

[Marlin]

That would be a volume vs. time design challenge, wouldn't it?

   No thermodynamics, falling water and rising vapor. The downdraft depends on cooling the air as well as entraining it to cause a downward flow. The designs I saw a decade ago were intended for coastal areas where colder water from deeper depths in the ocean were used to drive the down draft. Rising vapor from hot water in a nuclear plant cooling towers would counter the downdraft.

[peteshonkwiler]

i was thinking of the Second Law of Thermodynamics where, differences in temperature even out over time.
The time/volume design would most likely involve massive volume for the system. That would incorporate more time into the process. But, these towers are already designed to be almost a half mile high. Larger diameter should make the system operable, the challenge is the design.

[Marlin]

i was thinking of the Second Law of Thermodynamics where, differences in temperature even out over time.
The time/volume design would most likely involve massive volume for the system. That would incorporate more time into the process. But, these towers are already designed to be almost a half mile high. Larger diameter should make the system operable, the challenge is the design.

The tower is not a closed cycle system the second law does not apply.

[peteshonkwiler]

   No thermodynamics, falling water and rising vapor. The downdraft depends on cooling the air as well

My bad, sorry. I didn't realize you meant no thermodynamics were involved but only falling water and rising vapor.

[Marlin]

My bad, sorry. I didn't realize you meant no thermodynamics were involved but only falling water and rising vapor.

   Well not quite, as there is a transfer of energy in the form of heat, thermodynamics is involved. The transfer of energy is diametrically opposed. A cooling tower transfers heat (warm water) to the air causing an updraft that further adds to the cooling, if not just use a cooling pond. The downdraft tower uses cool water that transfers heat from the air in addition to entrainment causing a downdraft that is utilized at the base of the tower to produce power.

[peteshonkwiler]

Well, I said it would be a challenge. 

[Marlin]

Well, I said it would be a challenge. 

“The greater the obstacle, the more glory in overcoming it.”
― Molière

[HydroDave63]

“The greater the obstacle, the more glory in overcoming it.”
― Molière

Is it powered by Fusion?