Energy Tower: Power for 15 Earths?

Researchers have designed a product that its inventors claim could easily produce between 15 and 20 times the total electricity the world uses today. Not only that, it could also be used as a desalination device and may be able to reverse the effects of global warming.

Those are pretty big claims, but the researchers from the Technion - Israel Institute of Science seem confident that the "Energy Tower" could be a major solution to the world's problems. They've been working on the concept since 1983, and together have spent more than 150 man-years researching, designing, testing, and analyzing.

As project founder Professor Dan Zaslavsky explains, the Energy Tower works on the basic principle of convection: hot air rises and cold air falls. The 3,000-foot tall tower, with a diameter of 1200 feet, would take advantage of the heavy falling weight of cold air.

Any kind of water - from a sea or drainage ditch - would be added to the top of the tower. The water would cool the hot air at the top, and the heavy cooled air would sink downwards, gathering speed as it falls, and would be used to power turbines at the tower's base. The turbines would be connected to a generator, which produces electricity.

Because it relies on the sun for hot air, the Energy Tower is considered a type of solar power. Due to the original hot air required at the top, the concept would work best in hot, dry climates. The team has identified regions in about 40 countries where towers could work, including in the Middle East, Australia, North Africa, California, and Mexico.

The researchers also predict that the project would be cheap - electricity generated from this method would cost just 2.5 cents per kilowatt-hour, which is less than a third of the cost of electricity in Israel today. It's also cheaper than solar, hydro-electric, and wind power.

Zaslavsky explains that the tower design could also be used for water desalination, producing fresh water at only half the cost of existing desalination technologies. The water reserves might be used locally for a number of purposes, including desert irrigation, the production of bio-fuels such as sugar, or for fish farming - an energy-efficient form of agriculture.

Finally, the Energy Tower might help the Earth cool itself, and actually reverse global warming. "Hadley Cell Circulation" is a natural process whereby the earth cools itself, but it mostly occurs only near the equator. But by cooling air around it, often in desert regions, the Energy Tower could expand the effects of this global cooling process.

While the researchers are confident in their technology, they're still waiting for investors to finance the project before taking the next steps, including building a prototype. But in the end, they hope that the Energy Tower could be the key to providing cheap energy for large populations.

Via: Israel21c

Lisa Zyga
Science Blogger

Dec 30, 2007
by JEFF B (not verified)

Gimme a break

This is the dumbest idea I have seen in a long time. Using artificial (read energy-using) air flow when natural convection would already give you an upwards flow. This has already been proven in Spain (I believe). A large shaded area approximately 8 to 10 feet off the ground going into a tall cylinder is making them money so they can build another.
This idea uses water in places where water is not so readily available. The middle east???!!!! cmon !!

Jan 1, 2008
by Anonymous (not verified)

... ok

Concept is simple enough ... you're trying to develop a differential in pressure the column of cool air is simply out of balance with the light hot air at the bottom. So the hotter and dryer the location the better. The taller the tower the better. So a little proof of concept time ... Las Vegas Nevada ... Giant hotels .... Elevator Shafts. Run a 6" diameter pipe from the roof to the basement ... (The big trick here is that it has to vent out to hot outside air directly else the air-conditioned mass of air at the bottom would stop it. There is already a water supply on the roof. Some simple meters at the bottom would determine actual flows ... then scale up your ACTUAL FINDINGS with a little help from Mr. Bernoulli. The structure would be easy enough to build (I'm a structural engineer) it's size means it can be internally cable braced and the skin is just an environmental separator. So the same material used on Tensor structures would work ( I believe a reinforced kevlar fabric ) The engineer in me says "show me it working in the real world in a small scale" and then you can fund a slightly larger experiment and so on ... NO BODY is just going to say "Hey ... that's interesting let's just build it"

Jan 4, 2008
by sherman (not verified)


Ram-jets pump water without using any energy except the energy used during manufacture of simple tubes (i.e. pvc, abs) and construction/assembly of the units. The romans made water flow uphill in large quantities for short distances with zero moving parts. Even the wicking effect can raise substantial amounts of water a finite distance using no energy. Think in terms of stages rather than one long up-pump.These assorted Tower ideas appeared in print (science-fiction) in the 1940's and '50's with some (as yet unmentioned here) very useful side-effects. I personally don't like mega-structures because failure (inevitable) causes disasters. Smaller, replaceable components is smarter, allowing continual operation while replacement is occuring. I'd like to go on and on but I won't. I don't know why there is so much anger here.

Jan 28, 2008
by Evan Yares (not verified)

Not much water

We've had evaporative cooling towers in use in Arizona for some time.

All you need is enough water to slightly humidify the air. That makes it heavier, and it sinks through the tower, drawing even more air down with it.

The taller the tower, the greater the acceleration of the air.

The energy cost in raising the water to the top of the tower is fairly low, given how little water is required to sustain the process.

The damage from salt (if the water source is from the ocean) is about what you'd get from the air at the sea shore.

Mar 23, 2008
by Anonymous

Am I missing something???

Am I the only one who has noticed that when you go up in altitude it generaly gets colder on this planet not hotter. Yes hot air rises, but as you get further away from the ground which absorbs the heat from the sun then warms up the air it starts getting colder. Time to get off the computer and take a hike up a mountain. It doesn't get hotter and hotter as you go up. If nothing else pay attention the next time your on a plane and the TV says it -50 outside when you are over mexico. If it was not this way a solar updraft tower (which has been built) would not work because the air would be hotter at the top.

Jul 30, 2008
by Anonymous

it says man-years

check it

Aug 26, 2008
by Anonymous

Fact:There are thousands of

Fact:There are thousands of examples of water being moved several thousands of feet up and down in irrigation projects all over the world.

Cool it down a MOUNTAIN< awesome. You mean we don't have to build a 3000 foot concrete penis in the middle of the desert.?

A kill-joy comment:>What about all the birds that will be sucked into the cooling tower's intake?

Jan 15, 2009
by Anonymous


how much energy exactly is it going to take to get the water up there i mean 3000 feet holy crap and why exactly does the damn thing have to be so freakin tall no one explained that part along with why it has to be so wide GOD someone tell me you know what no one listen to me i have no idea what im talking about so anyone up for some HALO or anything