Solar Towers for energy and food.

mc_squared did a great post on a solar tower that is planned to be built in the desert of Arizona. The informative thread can be found here. Please check it out and S&F so more people become aware.

www.abovetopsecret.com...

An Australian company named EnviroMission is using an extremely basic principle of physics - the fact that warm air rises - to spearhead one of the biggest engineering projects the world has ever seen. The 2600ft tall, football field sized, "Solar Chimney" would generate 200MW of clean, renewable energy (enough to power 150,000 homes) with an expected structural lifetime of 80 years. The way the whole thing works is really simple: use a ginormous canopy (2 mile diameter!) to trap hot air warmed by the intense Arizona Sun. That air would then be (naturally) forced to escape up through the half-mile long tower in the center. As it rushes through the structure, it would drive turbines that generate electricity.

So I quickly did the math.

$750,000,000 to build. Powers 150,000 homes. That comes to $5000 per household. Not bad but it gets better. Spread the cost over 10 years and you are looking at $500 a year. I know I pay more that $500 a year in electric bills.. My average electricity bill for the year is around $3600 a year. Anybody see where I am going with this. Even after the 11 year mark the tower has an additional 69 years of life left after it had been paid for.

As for the cost - a cool $750 million. But it's expected the plant would pay for itself in only 11 years, as the design is so simple it has barely any operating costs. The beauty is that there are very few moving parts, so it doesn't cost much to operate, and because the area under the canopy heats up so much and there's still going to be a significant temperature differential between the bottom and the top of the tower, it can continue to produce power at night.

Because the canopy is acting like a greenhouse, it works at night and as an added benefit, it creates condensation. The condensation could be used to grow food under the canopy or collected for drinking water like desalination plants do.

Depending on the crop rotation you could feed a lot of people and provide power to a lot of people with just one of the proposed towers.

I would invest $5000 and bet 149,999 other people would to if it meant no more nuclear or fossil fuel power plants in AZ.

You forgot to add interest and bank fee's on the 5k over whatever the term of the loans are, probably not much different to buying a new car, would probably be 50$ a week or something for a 3 year payment term. And do these towers require any monitoring or maintenance or any body at all to manage them. Do they go back into the grid and credit those who own it equally or do they supply 150,000 homes directly from the middle of the desert?

If you can answer all of these questions and probably others maybe you should be putting together a business plan! ;p

Even if you had to pay interest on the loan of $5000 It would be less that what most pay each month to the power company. If they pay for themselves in 11 years it is $68,181,819 a year. Divide that against the 150k homes and each home only needs to pay $455 a year. That is just to pay for the cost of building it. I don't know what it takes to run something like that per year but it was stated that the operating cost was very small do to the simplicity of the design. No doubt they will charge more that $455 per year per household to make a profit.
As far as I know in Az , NM and Tx you do not get credit for "excess" power you generate. But this is a power company and I know they want to sell power to CA an NV.

I would expect something like this to take alot of time in planning, permits, connection paperwork, legal, loan approvals for 150,000 people, just getting signitures would take alot of time. Then construction, well even a house can take 6-12months to construct. I would expect you'd need at least a year or more just to get contracts to apply for loans, the entire project would probably take decades to complete, meanwhile you are still paying ur power bills.

But still worth doing, especially if you could get grants to help out. Of course grants come with 'conditions' such as 'prefered suppliers' etc pumping up the cost and whatnot. Wow im not trying to sound like a negative vibe merchant, but reality does it to me everytime.

OK, the energy production is explained, what isn't so much is the energy storage and delivery infrastructure, or does in feed the existing grid? I would imagine the turbines would require regular maintenance, and suck up lots of petroleum products, of course they could use graphite bearings I suppose, but there will be wear and parts would need replaced. I've seen these kinds of towers years ago but never really looked into the technology infrastructure. One concern that was brought up is to what effects would this have on the regular weather patterns of the area and surrounding area? I don't know. On the surface a half mile high hollow tower sounds like a colossal engineering undertaking, and Arizona is not far from a very active tectonic zone. Skyscrapers have an advantage of dampening structures within it's inner grid so I wonder what engineering mechanism is used to allow sway from wind and who knows what other kinds of pressures the structure will create itself. Just wondering I don't have any answers and I'm sure the structural concerns are addressed.

reply to post by Illustronic


It would feed back into the grid. Both proposed locations are near transmission lines according to Enviromission.

California has already purchased 30 years worth of power. Construction should start in 2015.

this seems like a good idea, but what about in colder cliamtes with long winters like northern europe,canada,russia where there wont be enough sun in the winter to run it long enough than

I've had several times to crisscross Arizona, Nevada and Utah for vacations. Each time I have to ask myself 'Why don't they put more solar plants out here?'

It's miles and miles of nothingness. Bright sunshine and sparce scrub brush.

You really can't comprehend the amount of area out there with nothing on it. You have to drive it to get the feeling.

reply to post by samkent


I hear you, and realize our (or my) American southwest is but a smidgen of the vast sunny areas around the world inside the Tropic of Cancer, the largest sunniest most barren deserts in the world around the entire globe. One would think just harnessing and focussing the ambient heat could run turbines without the huge towers, of course there is that water issue I suppose, or is it a water issue? Do you need water to run turbines? I hear there is a vast sea below the Sahara desert, I guess the oil is much more convenient though.

BTW, driving in the middle of Nevada at night, is sort of like space travel; you see headlights coming, they get a bit brighter in time, you turn off your high beams, and finally 20 minutes later that semi passes you, going 90 mph!