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Massive Solar Tower Planned For Arizona
inkscapee writes "It's simple, clean, low-maintenance, and cost-effective: using hot air on a large scale to generate electricity. No, this not a plan to use Congress to generate power, though that would certainly be an endless supply — EnviroMission will use air rising up a tall tower to generate 200 megawatts of electricity. The concept is simple: a giant greenhouse at the base of the tower warms the air. The warmed air rises through the tower and turns turbines, which generate electricity. The taller the tower, the faster the air moves, which increases power output. This structure will be a monster at over 2600 feet tall. It works in all weather, and if there is a feasible water source, food could be grown in the greenhouse."
But too bad - the greenhouse effect is a myth, as we all know.
McCain: How do we solve our energy generation problems? A series of tubes, my friends!
Bob Dole: Bob Dole agrees.
using hot air on a large scale to generate electricity.
Hence the "DC" in Washington DC.
This should make the back page.. over 2600 feet tall you say?
The mammoth 800-plus meter (2625 ft) tall tower will instantly become one of the world's tallest buildings.
Compensating for something there, Arizona?
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
There is no water left in Aridzona, so much for growing food.
This is, by far, the kind of tech we need to be investing in, preferably starting a decade ago. Genuine renewable, reliable power - are deserts hot? Yes? Let's make power from it! It'll be terribly uneconomical at first, of course, but it can improve given time. And it's worth trying out. It might not pan out, but it's sure as hell a better investment then 1.1 million in legal fees trying to surpress video games or whatever other legal action is popular at the moment.
So even if it's silly, go for it, Arizona - this is a much better investment then your immigration laws. In fact, triple your budget for this.
The idea is interesting, but it seems to me that a substantial portion of the solar energy is going towards gravitational potential energy - that is, lifting tons of air mass hundreds of feet in the air.
At some point, that air mass cools off, the air will want to drop back down towards the earth because of gravity. Seems like, in addition to generating 200MW on the 'exhaust' stack, they could build a second "cool air return" stack that generated power from the force of gravity pulling the cooled air back down to ground level?
Weren't they going to build this in Australia a couple of years ago?
What happened to that project?
What about this effort from 2008?
http://www.celsias.com/article/australias-solar-power-tower/
into cooler air, higher up. I wonder what the weather will be like near that tower after it goes into operation? This could be a neat experiment!
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At "176-194 F", I'm not familiar with any plants that grow well.
The efficiency of a heat engine depends on the difference between input and output temperatures, so this can't be very efficient, though efficiency is less important when the input is so cheap.
My initial question would be what happens when a hurricane lands near a 2600 foot tower perched on a giant greenhouse? Somehow the mirrors (concentrators) and water/oil tank configuration of solar power seems like a more resilient structure, if only for the fact that the mirrors are smaller and closer to the ground and you dont need a massively tall tower.
I'm not sure how 2600 did this, but it is a nice hack!
No, this not (sic) a plan to use Congress to generate power, though that would certainly be an endless supply
Yep, another old, tired, stupid and vacuous panning in the summary that you'd expect from a 14 year old who thinks he's massively clever. This is is what Slashdot has become.
It's in Arizona, what do they have to lose? :-P
"When information is power, privacy is freedom" - Jah-Wren Ryel
So you are saying the tower is constructed only by increasing carbon dioxide in an open chamber?
Odd, I thought it used heat trapped by passing through glass.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
I would see that growing food would be counter productive to generating electricity. In order to make maximum use of the facility, you want as much energy as you can to heat the air. And you want an air path with as little turbulence as possible to facilitate flow through the tower. Plants in the greenhouse would a) consume some of the captured solar energy, lowering the amount of heat imparted to the air and; b) provide obstructions to the flow of air. Certainly you can mitigate some of these effects. However, the constant influx of fresh air would take away a lot of the captured heat, which is the point of having a greenhouse to grow plants.
All of that aside, I wonder about the necessity of a greenhouse keeping plants warm in Arizona. I don't think warmth is as much a problem in Arizona as it is elsewhere but that's just me.
So there's no concern about moving vast amounts of hot air into the upper troposphere where there's ordianarily cold air? This will surely have a negative impact on global warming.
We're talking Arizona. Not much threat of hurricanes there.
This is a ridiculous idea. The only structure that is taller than 2600 ft is the Burj Khalifa (Burj Dubai), which is 2717 ft.
http://en.wikipedia.org/wiki/List_of_tallest_structures_in_the_world
The idea that we would build the 2nd tallest structure in the world for 200 MW is ridiculous. This doesn't even come CLOSE to being a top producer of energy per power plant. The top 10 power plants in the world all produce more than 6000 MW. Even the largest biofuel, geothermal and tidal plants currently exceed 200MW.
http://en.wikipedia.org/wiki/List_of_largest_power_stations_in_the_world
-molo
Using your sig line to advertise for friends is lame.
Yellowstone has some bacteria that grow at those temperatures, perhaps they could be molded into colorful bacon strips.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
hmm...looks a lot like something I once saw on Star Trek TNG (the pilot episode, no less): http://stavatars.net/images/locations/planets/planet_farpoint_station02.jpg
Anybody with knowledge on the topic: is there a way to add a Thermocouple element to this to increase the potential for power generation? Or is that an insanely expensive proposition or just a flat out bad idea?
1 (short ton / firkin) = 89.1432354 slugs / keg
It looks like the base of the buildings in The Jetsons... sounds to me like we will soon be selling real estate at the top of these towers... all the power for the building will be supplied by its own structure...
Would this work in the heat islands created by cities?
Impetuous! Homeric!
Ya'll got taken for a ride.
Stock opened at .66 this morning, it's now at .72 cents. Up 9.09%
Ya'll helped someone make a nice trade..
Thanks guys!
I know this is in a desert, but it will rain on rare occasions; what will they do with the water that falls on the structure? I imagine it would not be worth while to collect it and transport it somewhere, since it will be so rare. I feel like they probably have considered this, and I just want to know what decision they came to. Put it all in a big gutter, feed it into a huge sump (or a lot of little ones), or what? Also, what about dust buildup - will it get cleared by wind (like the Mars rovers' solar panels) or will someone have to go up there with a giant squeegee to clean it off every now and then? Again, I bet they have thought of it, and I am curious about what ideas they came up with. Maybe they only clean it when it rains? Maybe every time they do clean it, it rains the next day? Who knows?
From the images in the article it appear that the radius of the greenhouse will be greater than the height of the tower. How can that possibly be cost effective?
In 2005 EnviroMission said that the first solar tower would be up and running before year 2008 in Australia. That never happened.
Now in 2011 they say that it will be ready at the start of 2015 in Arizona. I hope they succeed this time.
Just Arizona itself. I consider that a win/win ;-)
People in cars cause accidents....accidents in cars cause people
It's not habitable. With a payback period of 11 years, it's doing pretty well, particularly for a renewable energy plant.
to generate electricity, but isn't a major hurtle for projects like this one the distance from where the electricity will be consumed? They're confining this to the desert, because of the daytime temps, but most power is being used on either coast, thousands of miles away.
Who would tend the crops? They're kicking all the migrant workers out.
Because the dubai tower is a hotel with needs lots and lots of cooling and other luxeries compares with a hollow tube that generates power not consume it and needs to compete with other powerplants that need fuel or hydro plants which needs enormous lakes...
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
To put things in perspective...this thing costs less than a single B-2 bomber, and about the same as a few 747s or a large cruise ship. Which is more beneficial?
The article claims the greenhouse base would be "remarkably good" for growing vegetables if there was a water supply, but also claims the temperature inside will reach 176-194 F. How does that work?
"and if there is a feasible water source, food could be grown in the greenhouse." Uh, this is the Arizona desert we're talking about here. Any living thing inside a greenhouse outside of December and January is going to be baked to a crisp. :)
Go away dummy.
Hmm
The basic technique is several thousand years old, and has been used to drive airflow for climate control in desert climates.
I believe there is a Spanish design consortium that has put together a similar proposal (they actually went for a double whammy.. add solar cells), but not nearly as tall.
As with ALL of these schemes, the problem is NOT that it can't work (it can), but do the economics work out ok. Right now, natural gas, coal, and oil are substantially cheaper, so unless some generous philanthropist decides to take some of their gains from the finance industry and invest in a low financial yield power plant, or the government subsidizes it, it ain't gonna happen.
There ARE some substantial technical problems too.. building a 1000 meter high anything is a chore, and if you expect it to stay up in thunderstorms, etc. the design will need to take substantial lateral loads. Traditional guying approaches would certainly be feasible, and the vertical column is going to weigh a heck of a lot already, so the downforce from the guys may not be an issue. Dynamic stability will definitely be a problem. One doesn't want a vertical version of the Tacoma Narrows bridge, after all.
Perhaps not as complex as actually building office/living space, but you do need elevators (unless you've got some burly stair climbing folks).
Phoenix is one of the largest cities in the USA.
a few years ago, there were people arguing that it was reasonable to tow asteroids to earth, then crash them into the ocean to produce a "cheap" source of metal ore.
I mean, seriously, the whole thing is a gee whiz popular mechanics thing - flying cars, the invention of the future, always have been, always will be
on whether or not there are any contractors for these planes in your district.
ORLY?
I mean I'm not a scientist, but if I understand the concept correctly, this is simply a giant chimney. ... the temperature at the top of the tower must be cooler than the temperature at the bottom of the tower.
It requires a temperature differential to work
They want to use a greenhouse type solar heater to keep the base hot.
Seems to me a thunderstorm, snow storm or cloudy day would probably shut it down, or at least greatly reduce output.
Of course putting it in the middle of the desert where such things rarely occur is a good idea.
reminds me of an idea I saw ages ago where someone was positing that we should build such a structure out of nano tubes along side the space elevator cable to vent excessive heat trapped by global warming and also of course, they wanted to put turbines on it, same as these guys.
Would it be possible to combine this setup with photovoltaic cells? Cover the all or part of the area and tower with photovoltaic cells to generate even more power?
Had you taken the time to even read the linked article, you wouldn't make such a ridiculous denouncement of something you absolutely do not understand.
Could be an interesting attraction. If the airspace isn't too restricted, sailplane pilots might have fun with it. (From what I understand, it's already a popular form of recreational aviation in Arizona anyways.) Seems to me like that would be an easy way to get a free thermal elevator ride for an entire afternoon of gliding. No looking for thermals when you have a reliable source for one in a given spot.
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I think they're just planning to use glass to trap the heat near the base of the structure.
unlike an office building, a solar tower will have massive temperature swings warping the structure at every day/night transition.
tell that to me in a REAL measurement system. not one that has developed out of someone's stinking appendages.
Read radical news here
Think energy, conservation thereof.
Adding a thermocouple would make the air flow slower (due to smaller heat differential), therefore you get less energy from the turbines.
I get it... turbine generators have really good efficiency and we've refined their use for over a century. But it seems to me that every worth-while method of power production uses them...
Solar Cells, and Lightning Rods seem to be the only methods I can think of that produce electricity without the use a turbine/generator combo but neither are viable for wide spread use. It seems to me that we'd do well to invest in methods of converting heat directly into electricity (giant Peltiers?) without the use of a turbine/generator. I would think doing so would theoretically make a number of our existing methods that much more efficient and perhaps open the door for other methods of power production.
Collector's Edition
A few years ago I worked at a power plant that had at one time the worlds tallest smokestack (now fifth) http://en.wikipedia.org/wiki/Mitchell_Power_Plant.
It's about half the height of the proposed tower. The smokestack had a massively wicked updraft at the ground level without any additional heat gathering skirting. There were signs on the doors into the stack warning you to not put you hands near the edges of the doors. The suction made the heavy metal doors slam shut and would take your fingers off if you weren't careful.
Overhead view: http://maps.google.com/maps?q=Cresap,+3,+Marshall,+West+Virginia+26041&hl=en&ll=39.829961,-80.815859&spn=0.010596,0.016029&sll=37.0625,-95.677068&sspn=44.52365,65.654297&geocode=FVD2XwIdi9Uu-w&t=h&z=16
When the power plant was built the answer to air pollution concerns was to build giant smoke stacks so you sent the smoke so high into the atmosphere it would be someone else's problem.
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How will this giant hollow tube and it's foundation react to being cooled and heated by 100 degrees (+/- depending on the season) every 12 hours?
With its 60% efficient design, it produces 200 MW.
Nuclear power plants are about 30% efficient, but we don't lop 700 MW off a rated output of 1 GW.
No, you can't grow food in the greenhouse for this purpose. Food (plants) will remove the heat energy collected and therefore reduce the efficiency. There is a reason why looking at a thermo map of cities that areas of heavy vegetation are much cooler then areas of concrete and glass. So you will have to build a larger greenhouse complex in order to achieve the same efficiency as having an empty greenhouse of concrete and glass in order to appease stupid eco-hippies.
Do scientists even proof read their theories anymore, or have the eco-terrorists zapped any intelligence from the scientific community? I am sure President Clinton will come along and want to paint the building white too in order to reduce global warming, and the eco-terrorist community will applaud him for such a great idea.
Seriously, society is getting dumber and dumber and by extension so too is the scientific community, especially when its about "green" ecology stuff.
Why not make the giant pipe out of a giant huge piece of nylon fabric like the Wacky Waving Inflatable Arm Flaling Tube Man. Then besides generating power it will amuse people living near by as the "Giant Wacky Waving Inflatable Arm Flaling Power Generating Tube Man"?
Relatively cheap, like this.
All of your power plants are nuclear or hydroelectric. Both cost vastly more to build and maintain.
Think of the advertising and sponsorship possibilities! I am Larry Ellison, and my Oracle giant green energy penis is 30ft taller than Steve Jobs's Apple giant green energy penis! NO! I'm Zuckerburg, and even tho I don't have much geek cred, MY facebook green energy penis is 30ft taller than Larry Ellison's Oracle giant green energy penis! Really, with all the corporate cash on hand right now in some of the techs, investing in a giant green energy penis size war might make some sense.
If my, admittedly aging, memory is right this idea is at least 50 years old. I think using Congress as a source of unlimited hot air is better because they are not limited by the Sun going down. Personally I would take a nuke plant next door over this monster... for 200MW?
They're going to build a giant glass bong in the desert?!!! I guess we know what the greenhouse is really for...
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Line the interior with solar cells and feed some of the electricity to HVAC systems which, at that scale, could air-condition an entire city around the perimeter.
The waste heat could then be dumped back into the main stack, making it even more efficient.
Haboob anyone? - so how does one flush one of these things....
at least we now know why Casa Grande exists.... ;)
It creates a low pressure zone at the bottom, which means there will be wind converging towards it. Maybe it will increase slightly the rain precipitation, which for Arizona would be good.
I looked at this last week. It looks good on paper, but has some serious problems.
First of all, I live in Arizona. and have practiced Engineering here for over 15 years.
The proposers need to take a few things into account.
First, Southwest Arizona is a moderate Earthquake area. Most of the rest of the State is mountainous. This thing will be an 800 Meter moment arm. It will have to be built to withstand the shaking. Every time Southern California quakes, we shake. Most of the Slouthern California earthquake faults have spurs into Arizona.
Second, the weather in Arizona is prone to several unusual effects. Yes, it gets hot here, but there is more than that. Because of the heat, there are dust devils and other wind effects that most designers don't expect. The International Building Code lists maximum winds of 60 MPH, but we have micro bursts. These are localized winds of up to 120 MPH. and higher. Every year there are wooden power poles that are snapped in two where a micro burst hits a power line. It takes quite a bit to break a 2 foot diameter tree trunk in two. To survive, this tower will have to be built to withstand winds of well in excess of 200 KPH (over 130 MPH).
Third, we have two thunderstorm seasons. the Monsoons are here right now. they usually start near the 4th of July. There is another storm season in December/January. This tower will reach high enough to be in the lower thunderheads. We don't have tornadoes here because of the mountains, but funnel clouds do form. They just get chopped up by the mountains. This structure will have to be able to withstand the shear forces of a thundercloud, perhaps even a tornado.
Fourth, the proposed use of the base as a greenhouse. Daytime shade temperatures in the Arizona desert reach 110 F most of June. July and August are a little cooler because of the Monsoon moisture, say 107 F with a relative humidity around 40%. A really hot day can reach 120 F. Most food crops cannot survive the temperatures. In a greenhouse, it will only be hotter. As a summer greenhouse, this idea will fail. Wintertime, it might make a good setting for plants, but so does the open desert. Farmers here have two growing seasons, Spring and Fall, if they can get the water. We rarely get a frost. Seldom see snow. At my house SE of Phoenix, I haven't see snowflakes for the last 7 years. Those I did see then didn't stick on the ground. The north Phoenix area and some higher elevation towns do get flakes and some dusting of snow. Up on the rim, in the mountains, they get several feet of snowfall each year. But not down in the desert. Arizona has several different climate areas.
If great care is not used, this project might just fall. Not fail, fall as in fall over. I hope that if this is actually built, the developer hires local Engineers to review it. The common design assumptions may need to be modified for the area.
I wonder how a sandstorm would effect this thing? We have them several times a year too. In the outlying areas, you can get your car sandblasted just by leaving it outside. There was a nice sandstorm a few weeks ago. The National Media called it a Hadood. Some Arabic word for sandstorm. There have been three so far this year. It's normal weather.
I consider that an insult.
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Technically interesting and probably feasible, but a non-trivial project to take on.
Considering your Governor makes up lies about immigrants and refuses to recant them for months of being asked to produce evidence.
Considering your Governor signed a law to imprison multitudes of people...which was written by her aides who have close ties to the private prison system in Arizona.
Considering McCain's complete abdication of anything resembling integrity to get reelected.
I'd think you'd consider those more of an insult since its being done in your name...
People in cars cause accidents....accidents in cars cause people
Yeah, those things are certainly true. And outside of my control, unfortunately. But I still consider your statement to be an insult.
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LightningPhysics and Effects
VLADIMIR A. RAKOV
AND MARTIN A. UMAN
Department of Electrical and Computer Engineering
University of Florida
Regarding the utilization of lightning energy It appears to be impractical to utilize lightning energy. Each cloud-to-ground lightning flash involves an energy of roughly 109 to 1010 J (Section 4.2). For comparison, the energy required to operate five 100 W light bulbs continuously for one month is 5 Ã-- 100 W Ã-- 3600 s Ã-- 24 h Ã-- 30 days = 1.3 Ã-- 109 J or about 360 kilowatt hours (1 kWh = 3.6 Ã-- 106 J), which is comparable to the total energy of one lightning flash. Even if it were possible to capture all the energy of a flash (this is not possible since the bulk of this energy is not delivered to the strike point but, rather, is lost to heating the air and producing thunder, light, and radio waves), one would need to attract 12 flashes to the energy storage facility in order to operate the five light bulbs for one year.
The probability of a lightning strike to a given point on ground is very low. For example, a 1 m2 area in Florida is struck by lightning on average, once in 105 years. A grounded structure protruding above the earthâ(TM)s surface is more likely to be struck by lightning. A 60 m tower located in Florida is expected to be struck by lightning at a rate roughly between once every other year and once every year (subsection 2.9.2). Thus, one needs 12 to 24 such towers covering a large area of 1 km2 or so to operate the five 100 W light bulbs, which is obviously impractical. Most of the United States experiences lightning activity that is a factor 2 to 3 lower than in Florida. As a result, the number of lightning-capturing towers needed to operate the five 100 W bulbs in areas of moderate lightning activity would be 24 to 72.
Thus the three main problems with the utilization of lightning energy (leaving aside the issue of energy storage devices) can be formulated as follows.
The power associated with a lightning flash is very high, but it is released in pulses of very short duration (of the order of 10â'4 â'10â'5 s). As a result, the lightning energy, the integral of the power over the short period of time, is moderate, comparable to the monthly energy consumption, 360 kilowatt hours, of five 100 W light bulbs.
Not all the lightning energy in a flash is delivered to the strike point. Using a typical value of energy per unit resistance (action integral) of 105 A s2 (Table 4.4) determined from measurements of the current at the negative lightning channel base and an assumed range of resistances at the strike point of 10 to 100 , we estimate the range of the lightning energy delivered to the strike point to be from 106 to 107 J, which is only 10â'2 to 10â'4 of the total energy. The capturing of a sufficiently large number of lightning strikes would require the use of a large number of tall towers, which is impractical.
Build the chimneys on a steep mountain and save some money in the process.
Why building a tower, when you can just build a 1000 meter long tube out of a cheap material ?
I like this other big scale wind idea too: http://www.maglevwindturbine.com/
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
Same story after five years...?
Don't forget base jumping from the tower.
And since we now have all these tourists and adventurers, lets stick a revolving hotel at the top.
Science is all about firing a drunk pig out of a cannon just to see what happens.
If the greenhouse at the base does any good, then the power cannot be independent of the weather, as claimed in the article.
These things work like big funnels - a huge area at the bottom and all the rising air channelled into a narrow space to provide a lot of moving air to run the turbines. What's on the ground wouldn't be very different from the tunnel houses tomatoes are grown in and not even all that different to what is outside.
However you're right in that it's a response about tying up land that shouldn't be needed but is to head off those "what about losing farmland" lines from those looking at an excuse to stop it. Lump it in with those that pretend that windmills tie up grazing land despite their being a total lack of giraffe ranches.
So basically you want to create a Meta-Power Plant. While I don't think they need the resonance aspect to it they could certainly add turbines to the outside to capture passing winds (they're doing this on some modern towers), solar underneath (instead of having a black painted floor even), and adding in geothermal (if feasible at that site) would be icing on the cake.
Solar cell power efficiency tends to drop off at temperature increases. Of course, if you can get them for cheap enough then it probably doesn't matter. I'd guess that building to carry the extra weight and stress of external turbines would not be a cost effective move. The goal is essentially a giant chimney, so anything that changes that is going to drive up costs quite a bit.
So they're taking 0.5% from that 100% and turning it into electricity. It isn't an EXTRA 99.5% added to the heat by the sun.
Your power station gets only 65% use and lots of that in off-peak time when you can barely give it away.
Ask France about how long you can run a nuclear power station before needing to stop it for a while.
This is not a new idea. I remember it on Popular Science in the 70's.
I've also seen it proposed running the other way. The tower is white to not absorb light, and you inject water at the top. The water evaporates as it falls, cooling the air in the tower. The heavier air, being more massive, creates a down draft. If you use the right sized droplets, you can use sea water, the water at the bottom is concentrated brine, and you have cold moist air flowing out from the tower. THIS can be used to effectively grow crops. One proposal suggested that the extremely heavy dew could water pasture for miles around.
Or you use the desert to heat water. Inject the water into the updraft. This reduces the lapse rate as the column of air rises, so you get more lift out of a given temperature. Hot water can be stored for night use. This requires a fresh water source. If you use sea water you are creating a plume of salt crystals down wind.
Not clear to me which mode makes more power.
Third Career: Tree Farmer Second Career: Computer Geek First Career: Teacher, Outdoor Instructor, Photographer.
Build "a giant fucking thing" in the desert. Then we can have the "giant fucking thing" gift shop, the "giant fucking thing" diner, and the "giant fucking thing" amusement park. The "giant fucking thing" would be a tourist attraction and I bet they could at least recoup a lot of the maintenance costs that way.
All that stuff would need electricity though...
And you complacency is an insult to all the people that make change happen.
Get involved and stop being a lazy fuck under the excuse 'I can't do anything'. OF curse they aren't outside your control.
Whiny bitch.
The Kruger Dunning explains most post on
why isn't that place in dubai pumping juice to my air conditioner? we can't be dependent on the saudis for oil forever; let's add another necessity for life.
True, it should be something that is easily figured out before anything is built so it should at least be explored and may be something that should be considered after it has been built since this is essentially a prototype and may have all sorts of interesting structural and atmospheric challenges.
I'll meet you at the intersection of "Should be" and "Reality"
I'd say you're the one being complacent, by tossing childish names at people you know nothing about in a conversation you weren't a part of.
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