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Massive Solar Updraft Towers Planned For Arizona
MikeChino writes "Australia-based EnviroMission Ltd recently announced plans to build two solar updraft towers that span hundreds of acres in La Paz County, Arizona. Solar updraft technology sounds promising enough: generate hot air with a giant greenhouse, channel the air into a chimney-like device, and let the warm wind turn a wind turbine to produce energy. The scale of the devices would be staggering — each plant would consist of a 2,400 foot chimney over a greenhouse measuring four square miles. The Southern California Public Power Authority has approved EnviroMission as a provider, although there’s still plenty of work to be done before the $750 million, 200 megawatt project can begin."
They should build it in Washington DC
"Be kind, for everyone you meet is facing a great battle." - Philo of Alexandria -
This will bankroll people's salaries for YEARS before it is ever (not) built.
How does this help again? Hookers and blow and all that?
I want to delete my account but Slashdot doesn't allow it.
these couldn't be built for a small fraction the price by using an atmospheric vortex engine instead of a tower.
Present day. Present time.
A 4 square mile greenhouse in the middle of the dessert? No, that shouldn't be expensive to maintain... and keep the glass panels clean and unbroken in!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Is there some efficiency to be gained by building a four square mile device over, say, 2560 one acre devices? Energy efficiency? Cost? It seems like there's a lot of risk in building one giant unit.
-Peter
Do you suffer from MUS (Multiple Urine Streams)? Are your trips to the bathroom blighted by UPTs (Unpredictable Piss Trajectories)? Well, fear not, you are not alone. Research has shown that in 99% of cases, MUS and UPTs are caused by two factors; either debris trapped in your glans, or a poorly configured foreskin. Well, your toilet seat soaking days could now be over, as a revolutionary GIMP plugin written by prolific rock-ballad artist Meatloaf will solve *all* your bathroom carpet dampening needs.
Simply use your favourite digital camera/camera phone to take a photograph of your penis before you are about to urinate, transfer it to your Linux-based laptop, and Meatloaf's incredible software processes the image using advanced techniques like Neural Nets, Stochastic Sampling and Genetic Algorithms to analyse the configuration of your bell-end, and give advice helping you to avoid both MUS and UPTs. The software is also written in 100% x86 assembly language, taking advantage of Meatloaf's decades of experience working with Intel's modern processors, to deliver accurate results in seconds.
Order it now, and banish piss soaked carpets from your life forever.
This thing does not ADD any energy to the atmosphere. It EXTRACTS energy from it.
___
If you think big enough, you'll never have to do it.
This DOES (essentially) reduce thermal energy in the atmosphere.
:)
Typically, the solar energy just heats up the ground, and also bounces around in the atmosphere and heats it up. This thing works by trapping the energy in a small area (greenhouse) and then using some of that heat to generate electricity. By the time the air is pumped out into the open atmosphere, it has less heat energy than if the thing wasn't there to begin with.
This really boils down to being just like a photovoltaic panel. Rather than the Sun wasting its energy heating up the atmosphere, we use the energy to make electricity... which we then waste by turning electricity back into heat which heats up the atmosphere.
-Bill
A nuclear plant would use maybe 50 acres and produce a gigawatt. I think the capital expense is comparable. What is the benefit here?
Regards,
Jason
Back in the 70s there was a proposal to build a very tall cylinder (1 mile or so), inject water mist at the top, and let the resulting downdraft drive a turbine a ground level. Interesting idea, fairly well developed and into the engineering stage. Of course, nobody funded actually building one. The engineer who designed it couldn't overcome the skeptics, and nobody thought it would be competitive with cheap natural gas/oil-fired generators.....
$750M for both, or $375M each, eh?
The KLVY mast is just as tall. $500K in 1960 dollars is about $4M in today's dollars. I'd have guessed that you could build three of those and wrap them in plastic, with a turbine suspended among them. Greenhouses aren't millions of dollars per acre - using the half-assed technique I used to build my greenhouse the plastic sheeting (10-year polycarbonate) would cost under $150K/acre. And they'd be really dumb to buy it from Home Depot (I learned everybody is dumb to use the special order desk at Home Depot).
Maybe their plans are engineered for very-long-term quality. It would probably be easier to get funding for $25M towers which can start making a profit after a few years, though.
Disclaiemr: I have no idea what I'm talking about.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
What precisely do you think they're trying to do? Where do you think this thermal difference comes from exactly? Every single process that generates usable electrical power generates thermal energy. Simple thermodynamics dictates that a process must be less than 100% efficient and must create more disorder than order. So instead of converting coal and air into CO2, electrical power and heat; we're converting solar thermal energy into electrical power and waste heat. The thermal energy is already there and is going to waste otherwise.
Sigs are too short to say anything truly profound so read the above post instead.
Net zero. When the energy extracted is used (ie using a toaster) that energy would be released into the atmosphere.
Why not use the sewers? They're supposed to be enclosed anyway -- they're already pretty hot, and if we built them correctly, we could compress, burn, and expel the gas -- which would maybe produce more energy and utilize existing infrastructure than this idea.
#fuckbeta #iamslashdot #dicemustdie
In a science fiction story of the 50's whose author I can't remember there was an eccentric inventor named Shorts. The character was used in several stories. One involved the invention of "Shorts towers" of exactly the sort described. But they had multiple purposes. The first was erected in a desert with an inflatable dome as the greenhouse. Not only was power provided - so was water, through condensation as the hot air ascended and cooled off. The humidity is low, but there's some water vapor to condense.
Or they were used in reverse, as city air conditioners. Dome a city. Erect a tower. Use fans to bring cold air down from altitude. You need the fans because of the density gradient.
Does anyone remember the story and author?
Sounds almost as promising as the tidal power generator my local PUD has been working on not building for years. I am sure that any day now they will be right around the corner from a great beginning.
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
4 square miles of solar panels in the desert? No that shouldn't be hard to expensive to maintain and keep all those uber expensive solar panels clean and unbroken
This would be awesome for unpowered aircraft. Perhaps they could provide/rent services and equipment. Probably hella dangerous though.
Today's Solar Cells cost around $3/Watt. With $750 Mil, we can generate about 250 MW of power in an area that is less than 4 Sq miles. So Why does this make sense?
No, no, no, you have it all wrong!
Amerika will pay Australia to buy from an American corporation. The American corporation will in turn import all the raw materials from china and help the Australian firm find a bunch of minimum wage mexicans to build the thing.
The only question is... which south american country will supply the hookers and blow for this project?
This sort of news upsets me... Why do we spend countless dollars on searching for more energy if the basic problem is not addressed first: There are too many humans and until we figure out how to control human population growth we are doomed sooner or later.
Human population will reach 9 billion this year. If every nation strives to become a developed country and offer things like air conditioning and cars to almost everybody, we will keep running out of energy regardless of what methods we use to find it. There will be a point in time when all our efforts to get new energy will be exhausted. Then there will be a war for basic stuff like water. At that point our weapons will be so advanced that we will probably be starting from scratch after the war is done.
The solution is simple -- before fucking with the planet and spending billions of dollars on green efforts, work to limit the population growth. Come up with a creative formula that encourages people to have fewer kids and who knows perhaps in a century or so we'll be able to reduce human population to something that Earth can sustain.
I wonder what the environmental impact will be of injecting hot air into the atmosphere at 2400 feet... given that the plume will probably rise a fair bit higher again due to it's momentum...
profit! Half mile high tower? Pffft
Hey genius, where do you think the thermal energy that's being collected came from and went to in the first place?
George W. Bush is already scheming how to dodge the updraft.
If built, the towers would be the second (and third) tallest structure on earth, behind the Burj Khalifa that opened this week.
You keep using that word...
# cat
Damn, my RAM is full of llamas.
There is reluctance to attempt to reproduce a phenomenon as destructive as a tornado, but controlled tornadoes could reduce hazards by relieving instability rather than create hazards. A small tornado firmly anchored over a strongly built station would not be a hazard.
This is some serious out-of-the-box thinking, so I will resist the urge to take a cheap shot at it by asking, "What could possibly go wrong?"
This intriguing idea deserves further study and maybe a pilot plant.
That that is is that that that that is not is not.
Umm, hate to mention it to you , but this is using energy already available, not changing matter to energy, or using combustables. Sunshine is Free !
Do you suffer from MUS (Multiple Urine Streams)? Are your trips to the bathroom blighted by UPTs (Unpredictable Piss Trajectories)? Well, fear not, you are not alone. Research has shown that in 99% of cases, MUS and UPTs are caused by two factors; either debris trapped in your glans, or a poorly configured foreskin. Well, your toilet seat soaking days could now be over, as a revolutionary GIMP plugin written by prolific rock-ballad artist Meatloaf will solve *all* your bathroom carpet dampening needs.
Simply use your favourite digital camera/camera phone to take a photograph of your penis before you are about to urinate, transfer it to your Linux-based laptop, and Meatloaf's incredible software processes the image using advanced techniques like Neural Nets, Stochastic Sampling and Genetic Algorithms to analyse the configuration of your bell-end, and give advice helping you to avoid both MUS and UPTs. The software is also written in 100% x86 assembly language, taking advantage of Meatloaf's decades of experience working with Intel's modern processors, to deliver accurate results in seconds.
Order it now, and banish piss soaked carpets from your life forever.
I tried this and now my penis looks really blurry and pixelated.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
You are completely wrong. At some point there will be a scale where the chimney will pull ahead.
Double the area of photovoltaics and you only get twice the energy. As turbines get larger the losses are proportionally smaller, and when you have more moving air you can have more blades optimised for different speeds. It's a comparison of a rising curve for the chimney vs a line for the photovoltaics. After the point where they cross the chimney gives you more energy for the area.
My gut instinct is that the environmental impact would be nothing - after all, hot air is rising from the desert in columns, naturally, *all the time*. They aren't adding any additional energy that wouldn't be there anyhow - all they are doing is trapping the hot air which would be rising *anyhow* up into the atmosphere, and *extracting* some of the energy from it.
On the note of momentum - if you are using the air to drive turbines, wouldn't you actually be significantly *reducing* the momentum? After all, as the air rises, and then collides with the turbines, it is imparting some of it's momentum into the turbines.
Disclaimer: I'm not any sort of expert on this stuff. Ignore me or laugh at me as you like.
I'm dubious about this. The scale of the thing is staggering, and it's hard to believe it will produce a better electrical output than if you spent a similar amount of money building a molten-salt solar thermal plant instead. Unlike molten salt solar thermal, this won't make electricity at night.
The one thing that makes this interesting is that it combines a giant greenhouse with the energy generation. If you can somehow make the greenhouse part very profitable (growing exotic fruit that is expensive to transport, or some such) then maybe you might have a payoff to match the expense. Maybe. But I'm dubious.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
Wouldn't a Concentrated Solar Thermal power plant be a better use of the land, producing more energy and probably costing less too?
Spain is doing something similar. But different.
http://www.power-technology.com/projects/Seville-Solar-Tower/
No sig for you. YOU GET NO SIG!
You picked the ONE example where your system is sun->solar panels->electricity->heating toast.
But there are MANY other uses for electricity that don't dissipate 100% of their energy in heat.
What does the term energy efficiency mean to you? That, is if our electronic devices are more efficient than the solar panels used to power them, we would be removing heat energy from the atmosphere.
Anyone have the figures for the cost of conventional generating facilities that, you know... Work when the sun's not shining, too?
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
...we sure don't know how to make windows that don't break easily. Ever hear of Plexiglass?
Over-the-top Response Guy! Giving "Over-the-Top Responses" since 1970.
Just curious... would placing solar panels inside the greenhouse be of any use? Do solar panels not work behind greenhouse glass?
It isn't clear to me that this plant will cool the air. A greenhouse has the effect of warming the earth, because solar radiation is transmitted, but thermal radiation that would have passed through the atmosphere is retained. You say that the thermal radiation heats the atmosphere, but that is not completely true. Some of it passes through the atmosphere without being absorbed. The increase in absorption due to carbon dioxide in the atmosphere is hypothesized to be a source of global client change. This hypothesis would be trivially proved false if all the thermal radiation from the Earth's surface heated the atmosphere. This greenhouse is certain to prevent more thermal radiation from escaping into space without absorption than the atmosphere on its own.
Furthermore, any heat that the turbine converts to electrical energy will be converted back to heat in a very short period of time by appliances connected to the grid and by line losses - nearly 100% of it will be heat within a minute of conversion to electricity.
A giant sun tower or two in Arizona is an interesting idea. But it makes more sense to build a huge lightning capacitor.
There's this place in Arizona where lightning strikes are common and happen nearly every night. Something in the atmosphere, the heat, and humidity.
So why not dig a huge hole in the ground, fill it with aluminum foil and electrolytic, then quickly and carefully build a huge lightning rod. The lightning will constantly arc to the giant million farad capacitor in the ground. It gets recharged up every night and the 'supercap' powers a small city or suburb.
Electricity directly from the sky to your PC!
At 1kw/m^2, the input power is over 10 Gwatts. That means the power efficiency is less than 2%.
And people complain about the area needed for photovoltaic sites? Ridiculous!
This DOES (essentially) reduce thermal energy in the atmosphere.
Possibly, but someone would have to run the numbers to make certain. Personally, I have my doubts, at least about the direct reduction in thermal energy. A lot of the solar energy that reaches the Earth is normally reflected away without being converted into heat, particularly in cloudless, bright-floored desert areas. This project would instead convert much of that energy into heat and then dissipate it into the atmosphere. They say right in the OP that it uses a greenhouse concept, and if you had a really large number of these, it would essentially cause a global greenhouse effect without involving any greenhouse gases.
On the other hand, a net reduction of thermal energy in the atmosphere could arise from a reduction in greenhouse gas emissions made possible by the use of these facilities, i.e., an indirect benefit.
You people have no sense of scale.
The heat our civilization directly produces is utterly insignificant in terms of climate change. The issue is that our carbon emissions act as greenhouse gasses and alter the entire earth's energy balance, greatly amplifying the heat-trapping effects of the atmosphere.
It's solar radiation that's warming the planet, not the heat we directly produce.
This plant doesn't cause any carbon emissions. Even if it does warm the atmosphere, the effect is insignificant next to the greenhouse gas emissions that don't need to happen to generate the same amount of power.
Such as? Every electrical device ultimately releases all of the energy it consumes as heat or in some form that eventually becomes heat. Take a fan for example. Some of the energy it consumes is dissipated in the motor directly as heat. Some is used to move air but that moving air eventually slows down due to friction ... which generates heat. Even the noise from the fan gets converted into heat in your room.
So we have given up and are going to proactively warm the earth's atmosphere directly now?
Instead, do the thermal collectors on a Coal/gas/Nuke power plant. The reason is that it would be cheap to add to the large number of SMALL coal/gas plants running around the world and then lower the demand. The approach that you are talking about requires more collectors to hold the storage for nighttime. The approach that I suggest will also require no other extra infrastructure costs, other than adding the collectors.
I prefer the "u" in honour as it seems to be missing these days.
How will we generate the 1.21 gigawatts of electricity we need?
Unfortunately we've been buried under decades of "too cheap to meter" and "clean" lies by an industry that spends orders of magnitude more on PR than R&D while picking up enormous amounts of government welfare. In recent years however there have been organisations outside of the nuclear lobby that look as if they will make it a commerical reality. Examples are non US solutions like pebble bed, accelerated thorium and startups like Hyperion (lots of little modern submarine style reactors instead of one big dangerous dinosaur from Westinghouse). It's time for all the liars to get buried by those that really did the R&D.
Don't blame the hippies, they really didn't have the political power you credit them with. The nuclear industry of the 1970s simply showed they were a waste of space and they are still stuck in the 1970s.
Err... not so.... There are NO uses of electricity that do not dissipate with 100% efficiency to heat eventually. You may cheat for little while by storage (charge a battery, pump water to high level, run a flywheel) but in the end it all goes into heat. Sorry.
I find it interesting how this is essentially a way to use waste heat generated by sunlight. I wonder if the design takes extra advantage of that fact.
For example, one could have the fans drive long shafts to put the generators closer to the cold air inlets. Not only would this be beneficial in keeping the generators cooler, the excess heat generated would create even more power. Another idea is to add some heat intensive industrial process near the inlet. The waste heat from the facility would just add to the energy. If the process runs on electricity one could again boost the effective efficiency by using the solar tower's electricity to power the process. A computer center might be a decent source of waste heat, but I don't know if silicon technology gets hot enough to be practical. Maybe if it's used in a pretty cold environment.
Chris Mesterharm
Your mind is still in the "small is beautiful" rut. Nuclear power plants are big because big plants are more efficient and easier to regulate, which makes them cheaper and safer. Hyperion is a crock.
The production of aluminum from aluminum oxide, or plenty of other chemical reactions moving something from a lower to higher energy state. Granted many of those result in some kind of use (synthetic fuels are designed to be burned, or if it's a pharmaceutical by metabolism and so on) that would release the stored energy as heat, but it isn't necessarily so. Like all that aluminum around you that you aren't using as a fuel source.
The enemies of Democracy are
Copying my reply to another poster:
Direct solar thermal plants need an insane amount of plumbing and a zillion little motors to run the heliostats to point the mirrors at the sun.
This updraft machine is definitely going to have lower thermodynamic efficiency (Carnot's law guarantees it), but on the other hand it has far fewer moving parts.
The project will decimate 2000 acres of desert habitat for 200 megawatts output. Palo Verde nuclear power plant, also in Arizona, spans 4000 acres of desert and produces 3.2 gigawatts.
Nuclear power is 8x more efficient in land use alone.
Ever see aluminum burn?
You've misunderstood.
You still have the "big plant" but made up of a lot of little reactors collectively heating up the steam for very large turbines. A big Chenobyl style steam explosion spreading fuel everywhere or even just water in the radioactive loop can't happen in that situation. A current example is the pebble bed powered plant that should be finished by now in China. However the main problem with Westinghouse etc is that they are more than twenty years behind even South Africa and some good ideas have come up over the last few decades.
Electrical energy -> increased gravitational potential energy, not heat.
Though arguably, counter-weighting means any overall increase in potential energy is likely outweighed by friction losses (i.e. heat)
.
Why would anyone engrave "Elbereth"?
You picked the one example where your system is sun->solar panels->electricity->running simple electric device. (although this is a very common case)
Processing ore such as aluminium ore consumes electricity and generates much less heat energy than is input. Basically chemical process that is endothermic will do this.
I certainly sounds neat but what are the consequences of adding hot air that high above the ground? EIR? Is this thing understood at all? There are such things as unintended consequences and it's not like this is a phenomena that happens in nature all the time.
Just wanting folks to think things through a little?
Like can they grow some marijuana or somethign, it could pay for itself.....
Greed weed for green energy, let the silly pot heads who want to save the earth subsidize the saving of th earth and get high at the same time, win-win.
Tsukasa: All I really want, is to be left alone...
Westinghouse makes submarine reactors, by the way.
Note that the solution to nuclear power phobia isn't thousands of nuclear power plants instead of hundreds of them.
Unfortunately, AGW will have to get a great deal worse before we can think about actually adopting a zero emission baseload.
"I do not agree with what you say, but I will defend to the death your right to say it"
Ever see aluminum burn?
Yes. Is all aluminum burning? No. Then is the supposition that all electrical devices release all their energy as waste heat true? No. Some of it can be stored for essentially arbitrary periods of time (the fact that aluminum burns being the big hint that reversing the process involves putting energy in). Eventually everything is heat. But only for definitions of "eventually" that have nothing to do with the original question of net heat in the atmosphere.
The enemies of Democracy are
The thermal energy is already there and is going to waste otherwise.
"Waste" is probably the wrong word here - the thermal energy is stored as potential energy, the question of "waste" is a purely economical concern, relevant only if you view all available resources as there to be exploited.
Man who leaps off cliff jumps to conclusion.
Some is used to move air but that moving air eventually slows down due to friction ... which generates heat.
I'd like you to explain how moving air creates heat during the next blizzard.
Man who leaps off cliff jumps to conclusion.
I use Westinghouse as an example becuase they will happily sell you a Chenobyl era reactor painted green and pretend it's new. They spend almost nothing on R&D and the only thing they actually build that is a new design came from Los Alamos paid for by the taxpayer. They are on welfare. It's best ignoring their PR and moving forward even if that means buying something from outside the USA.
It's going to waste because we're currently using coal to provide power that this naturally occuring thermal difference could provide. I believe that it would be preferable to use the clean renewable resources we have before resorting to our nasty high sulfur coal deposits. Waste heat is also a thermodynamic concept wherein the energy in a thermal difference that isn't put to work in some manner becomes waste heat (the ordered thermal difference becomes chaotic and thus high in entropy and therefore spent)
Sigs are too short to say anything truly profound so read the above post instead.
Basically yes, it starts oxidizing right away and releases energy in the process. Burning aluminum is just really fast oxidation. I was pointing out that turning aluminum oxide into aluminum is basically just energy storage, which you can see by burning it.
No, the vast majority of electricity use ends up as waste heat pretty quickly, electronics, lighting,motors, heating (obviously), cooling etc. Comparatively little is stored long term and doing that usually involves a lot of waste anyway.
This will never get built.
Even a very small wind will topple anything that goes up that high.
If this thing is so great why aren't they building it in their own backyard?
Electromagnetic radiation may be a long, long way from the surface of this planet before it becomes heat. (This does not invalidate your point, just modifies it a little.)
You guys do know this looks like something some ignorant independent inventor figured out, then the Australians got it from him (no royalties). Probably an American inventor. That way the millions go to Australia and makes the aborigines there look real smart, when all along it was the American who crossed the Finish Line eh? hahahahahaha I kill me. Watch the shells closer boys and you'll see they are being moved by Satan.
Personally I prefer injecting a volcano with water and driving a turbine with the steam. Apparently these days they're using sewage effluent instead of water, which prevents river pollution as a fringe benefit. No, you don't really need a volcano, but you do need something like it for geothermal energy to work.
It's cheaper than coal (3.5c vs 5.5c/KWh), doesn't get in the way, has minimal pollution issues compared to other systems. And it's available 24/7. Geothermal provides the US with 3,040MW of energy now, and nearly 4,000MW more are in development. While this is a tiny fraction of the current electricity generation there's no reason why we can't do more of it. Wind power by comparison generates 10 times as much power and is claimed to cost "less than 5c/KWh" and DOE claims that up to 20% intermittent wind power can be integrated to the grid for as little as 0.5c/KWh additional.
As further fringe benefits the dry steam produced can be used in Hydrogen production, as a heat source for homes and greenhouses, and in other manufacturing or agricultural processes. We're not really getting everything we can out of the geothermal steam that's generated now.
On the downside the East coast of the US is out of luck unless they drill deep, because they're seriously lacking in subsurface temps.
Help stamp out iliturcy.
A sign bearing the subject line, "Los Angeles City Limits" was stolen from the border of LA and hung by the side of the road in my home town in Bishop, CA some 260 miles away. It stood there several years. It was a political statement of the political reach of the LA Department of Water and Power, which at that time extended to leeching every drop of water our of our formerly verdant vally - an engineering feat that required making water run uphill for several miles. Apparently since then the limit has stretched to Arizona.
To the point of your post: if the LA city limits don't yet extend all the way to DC, I misdoubt they will soon.
Help stamp out iliturcy.
evaporation of water would cool the air causing it to be more dense and sink down the tower. Just guessing, but sounds like what they were thinking of. I'm tempted to run the numbers, but maybe I can just ask wolfram alpha if it will work.
Basically yes, it starts oxidizing right away and releases energy in the process. Burning aluminum is just really fast oxidation.
You're right that combustion is just an oxidation reaction, you're totally wrong that all aluminum is burning. The outside layer that's exposed to air oxidizes immediately. That layer of aluminum oxide then protects all the lower layers from oxidation. That's why aluminum is generally considered rust-proof, that's why all the things around you that are made of aluminum aren't collapsing, and it's why when you want your aluminum to oxidize, like these guys, you have to make a special alloy to ensure that it happens.
And then there's plastics, and plenty of other stable chemicals who have energy stored inside them.
No, the vast majority of electricity use ends up as waste heat pretty quickly, electronics, lighting,motors, heating (obviously), cooling etc.
Yes like I said most is lost as waste heat. However you said it's all lost, and that's simply not true unless you're talking time scales beyond the lifetime of our planet. And in some cases, like aluminum production, most is lost as heat, but a quite significant 36% is actually going into the aluminum.
The enemies of Democracy are
No, it isn't stored. Energy from the radiation that strikes the earth would dissipate as heat, creating thermal updrafts, regardless. Harnessing it to use for productive purpose is much less wasteful.
"I assumed blithely that there were no elves out there in the darkness"
It's very annoying how many ignorant people throw around "solar" as a synonym for photovoltaïc.
Of course solar energy is actually responsible for all life on earth, and the ultimate source of power behind pretty much everything on the planet, but even solely in terms of conscious human implented technology solar energy is a broad field with photovoltaïcs being one small and relatively new and immature branch. Solar thermal technology is often far more efficient and less expensive, and just as much 'solar' as any other sort. The easiest and most efficient use is direct heating of water and air to displace the use of electricity to do the same job. Solar-thermal technologies also show some promise for power production, although this particular project looks to me far less likely to ever be useful than more conventional "power towers" which do not require such extravagances as 2400 foot chimneys (can you imagine the difficulty not just in building, but in maintaining that?) and convert solar energy to electricity using an extremely mature technology - the steam turbine.
The big savings for the forseeable future is still to be found not in using the sun to produce electricity at all, but simply to displace it. The $750million proposed cost of this plant (which is likely to increase several times before a single watt is ever produced by it) would be much better spent replacing electric water heaters with efficient solar water heaters, for instance. The 200 megawatts this plant is touted to eventually produce is only a little more than was displaced in the US in 2008 alone through installation of solar hot water heaters for domestic use alone (keeping in mind that market penetration for this technology in the US is still miniscule there is room for that to expand many times) and is only a little more than a quarter of what solar pool heating units displaced in the same year. Passive solar home design is another potential area of savings where the current market penetration is even lower, and the potential savings enormous.
Given the relative efficiencies and costs, it really makes no sense to me to be throwing all this money at speculative schemes for electrical generation while there remains so much more potential for displacement. Even confining this to the states where solar energy is most reliable and appropriate - the "sun belt" - the potential reduction in electrical usage is staggering and dwarfs what a project like this could possibly produce. One day when >90% of homes located between southern california and the florida/georgia/carolina coast have passive solar designs and thermosiphon hot water systems in place, THEN it might make sense to start throwing money at solar power generation on a large scale, but for the time being I just dont see it.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Friends don't let friends enable ecmascript.
Analog science fiction magazine had a story about these back in the sixties. The guy who invented them was named 'Short' so they were called 'Short Stacks'.
Man, I'm trying to find a citation but just can't come up with it.
The problem of overpopulation is already solved.
Their are many fast agents (Chemical Bio, Nuclear) as well as naturally acting slow ones (Famine, Pestalince, etc.),
When the time comes the soloution will apply quickly.
As extra benefit, anyone wanting to travel to Minnesota could simply be put in a Plexiglas cylinder and inserted into the tunnel. For the way back, they'd have to walk of course.
I suspect that this is not entirely true as an implementation of this concept would take steps to absorb much more of the light than the bare ground. I would be surprised if the power extracted from the generators (which will end up in the atmosphere anyway when that power is used) exceeds the amount of light that used to reflect off into space.
It was Glory Road. It was very educational. In it the Galactic Empress' commonest answer to every problem was: do nothing. Almost all problems solve themselves in time, given a wide enough view.
Well worth reading for this and a number of other reasons. It's the best representation of the "stream of consciousness" narrative I've seen, and it's a sexy good story. Actually I have a copy - and no, you can't borrow it. I wouldn't mind seeing what James Cameron could do with it.
You've got to give the Dean credit: whether it was stealing plot elements like the indifference of immortals to the travails of mortals or calculating orbits, the man was not afraid to do his homework.
/ Still hopes Hollywood stays away from Stranger in a Strange Land until I'm dead. I would have to go see it, and what they do to it would be sad.
Help stamp out iliturcy.
Assuming one could enter the tower above the turbines, wouldn't this be a nice way to launch with a paraglider?
After all, the sun is nuclear energy, and oil is just that stored.
But fooling with the exchange rates of solar energy to hot air do troubling things to long term models of air temperatures.
Help stamp out iliturcy.
It's a greenhouse. It has no heaters other than concentrating the sun's warmth. Have you and the moderators lost all sense of reality, forgotten what words mean, gone cuckoo?
Every time I think I've met and accounted for those idiots who confound my idiot-proof programs, I find that nature is preparing the batch right under my nose.
Infuriate left and right
I don't think that word means what you think it does. Even if the whole fucking planet were uranium, it would eventually run out, and that would not, therefore, be infinite. Yes, what we can find will last a VERY long time, but we will have to find something else, or somewhere else, to get our energy from some time in the distant future.
Additionally, reusing nuclear weapons material is all very nice, but it does rather encourage and "justify" the extremely expensive and wasteful nuclear weapons industry to make all new "better" ones to replace the decommissioned ones. Building and exporting weapons may currently be the USA's comparative advantage and singularly largest industry, but many, many of us humans our here in the rest of the world would really like it if you could find something better to do than promote and sell us ways to kill each other. This massive weapons export market is the proof that the USA government, through its non-regulation of weapons exports, is the world's single largest "terrorist" organisation. We're all scared stupid about Uncle Sam initiating another "democracy freedom" action in our once-sovereign countries.
Uranium from seawater is pure marketing fluff. Sure in theory you can extract from seawater, but not economically nor with a positive return on energy.
Even with current extraction + refinement+ enrichment, the energy return on energy investment for nuclear is only 10:1-20:1 depending on the study. Not all that great (solar is higher).
In fact there was a recent study suggesting we are nearing peak uranium production, given high quality EROEI mineable sources. (http://www.technologyreview.com/blog/arxiv/24414/)
Thermal solutions necessarily scale. There is no such things as "exponential scaling in thermal or nuclear sources" over a smaller device of the same type. Many small thermal systems are equally efficient to larger ones.
Two issues here: economics and physics.
Yes big projects often scale economically, but not with much thermal energy efficiency improvements. In this case the scaling is due to the cubic function of wind speed to power production. The higher you can build the chimney, power output goes up by exponential factors.
Photovoltaics scale just like a nuclear plant, or gas turbine. You put in two, you double the output. Several studies show them to be equal or better land use on a total resource basis to strip mined coal powered plants or mined nuclear... Oh yeah, and they don't have to take land space either as they can be placed on existing buildings.
2000 Acres for 200MW?!
You can use a old Los Angeles Class submarine nuclear reactor that is tiny ( it fit in a cylindrical section that was 33' by about 33') yet produced 148 TMW ( Thermal MegaWatts ) and this space contained the reactor itself, steam generators, primary coolant pumps, primary coolant expansion chambers then entire primary system
Now admittedly it had the volume and temperature difference of the ocean to condense the steam, but let me tell ya, even when injection temps where hovering in the low 80's it performed flawlessly for years and years on end.
Now EFPH ( effective full power hours ) was limited because the core was so tiny (however it did run on 97.3% Uranium) , but you could crank the thing at 100% of their thermal rating for about 3 years before is was time to re-core. Now of course no submarine runs around at 100% rated thermal power or anywhere near it all the time so the cores lasted for 15 years or longer.
So 10 of these little plants could pump out 1.5GW and take up about a football field less condensing towers. Because you have 10 of them at a station you can throttle the station down in 1/10th increments when demand is low and bring the station back up to rated power in a big hurry just by having the turbines spinning at a very slow speed and drawing very little from the core(s) and given that you might stretch the cores to 5 years or better.
Hey KID! Yeah you, get the fuck off my lawn!
Please don't pretend to completely misunderstand just to try to win some debating point - obviously by scale I'm talking about making BIGGER things and not two of the same.
Also f* the false insightful comment of "economics" where we are all suppose to nod sagely and agree - that's totally irrelevant until price comparisons of some kind can be made and it's going to vary wildly in different places due to different circumstances. We can only compare technology here and not what is cost effective in a paticular place since we are talking in general terms. In some places for instance land area is irrelevant, and in others it is the major cost. In some places cooling water is effectively free and in others you have to build stupidly long pipelines because there's not enough for both the power plant and the local irrigators.
I was living in Mildura until recently and we had a great hoo-ha for a couple of years about the multiple square km glasshouse they were going to build locally (at Wentworth if I recall correctly - the next town along the Murray). It's v hot there (regularly above 40C), v sunny (less than 300 mm rain annually) so an ideal spot for this sort of thing. However, it never happened, the next we heard they were going to build a smaller scale pilot (seems like it would be sensible to have thought of that first), and still nothing happened. I've never heard them say they weren't going to build anything, but it looks like that is the result.
In other words, don't hold your breath for this to actually happen.
Si hoc legere scis nimium eruditionis habes.
Hiryu Shoten Ha!
I think it is almost 10 years since I first read about it. At first I was very enthusiastic but now I am bored of the stories that talk about these towers at the future tense...
The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
Won't such a concentrated injection of hot air high in the sky generate a massive cloud cover right above the solar installation? Must be fun to fly in the neighborhood of these things with a glider though :)
int main(void) {while(1) fork(); return 0;}
They will replace the light brown/orange/whatever of the desert with something black, to trap more heat. This will double the heat that stays on Earth (and is not reflected to space)
Radio antennas do not release the energy as heat - or at least, not heat that remains on Earth but energy that is beamed outside Earth
Combine with desalination plant. Paste in Sahara desert. Use water for drinking and irrigation. Profit.
Religion is what happens when nature strikes and groupthink goes wrong.
http://en.wikipedia.org/wiki/Solar_updraft_tower#Prototype_in_Spain
Prototype in Spain
In 1982 a small-scale experimental model of a solar chimney power plant was built under the direction of German engineer Jörg Schlaich in Manzanares, Ciudad Real, 150 km south of Madrid, Spain; the project was funded by the German government.[10][11]
The chimney had a height of 195 metres and a diameter of 10 metres with a collection area (greenhouse) of 46,000 m (about 11 acres, or 244 m diameter) obtaining a maximum power output of about 50 kW. However, this was an experimental setup that was not intended for power generation. Instead, different materials were used for testing such as single or double glazing or plastic (which turned out not to be durable enough), and one section was used as an actual greenhouse, growing plants under the glass. During its operation, optimization data was collected on a second-by-second basis with 180 sensors measuring inside and outside temperature, humidity and wind speed.[12]
For the choice of materials, it was taken into consideration that such an inefficient but cheap plant would be ideal for third world countries with lots of space - the method is inefficient for land use but very efficient economically because of the low operating cost. So cheap materials were used on purpose to see how they would perform, such as a chimney built with iron plating only 1.25 mm thin and held up with guy ropes. For a commercial plant, a reinforced concrete tower would be a better choice.
This pilot power plant operated for approximately eight years but the chimney guy rods were not protected against corrosion and not expected to last longer than the intended test period of three years. So, not surprisingly, after eight years they had rusted through and broke in a storm, causing the tower to fall over. The plant was decommissioned in 1989.[13]
Based on the test results, it was estimated that a 100 MW plant would require a 1000 m tower and a greenhouse of 20 km2. Because the costs lie mainly in construction and not in operation (free 'fuel', little maintenance and only 7 personnel), the cost per energy is largely determined by interest rates and years of operation, varying from 5 eurocent per kWh for 4% and 20 years to 15 eurocent per kWh for 12% and 40 years.[14]
Bring back the old version of slashdot.
Wouldn't it be cheaper to put a single politician in the base of the tower to act as the source of hot air, rather than build 4 square miles of green house?
Third Career: Tree Farmer Second Career: Computer Geek First Career: Teacher, Outdoor Instructor, Photographer.
Exactly. Big win compared to other methods of powering that toaster.
I'd like you to explain how moving air creates heat during the next blizzard.
I'd rather stay out of that blizzard, but it's true. It does create (a really tiny bit of) heat.
You people have no sense of scale.
This is really something that needed to be said, and it deserves to be modded up to +5. Heat is not an issue, it's only carbon emissions (and methane, to a lesser extend) that really matter..
You could do that with the 4 plants, then throw the waste heat into the base of one of these 2000 acre large chimneys - so output would rise during the day.
This would have the benefit of making the reactors hard to find for any protesters...
$3750/kW is absolutely insane.
A Westinghouse AP1000 nuclear plant costs $1000/kW...
Wind mills do not work that way!
1. The energy calculatiosn were done by a German consulting company almost 6 years ago, and the numbers look good.
The software they wrote allows different sizes of systems to be inputted and metrics drawn out.
2. But there are a few issues.
a. The price of the tower both in energy and cost. The tower must be make out of concrete for structural reasons. A one kilometre high concrete tower is a very costly initial upfront cost.
Also the cost for cemenet is very high now and the carbon output is massive. Concrete is a hugely inefficient material both from an environmental and ecconomic viewpoint.
b. Its all or nothing. By this i mean that for a PV or thermal solar solution you can expand your farm at stages. This makes projects much more viable financially.
But the tower is monolithic.
I woudl like to see a design that is not monolithic, and i think it can be done. The concrete tower coudl be modular and extra height segments are just helicoptered in.
The greenhouse of course is modular, as are the water filled piping at the base of the greenhouse.
The other big advanateg and i what i think woudl help this technology make progress woudl be for it to be residential scale.
I dont knwo what the energy calcaultions woudl reveal on a 3 story high tower that is building integrated with a glase house around it.
As an architect i would like to see buildings designed for this, and the living spaces build around the tower.
Often you need a riser in a building anyway for your plumbing, ventilation and electrical. It makes the cost of all these service installations much cheaper when you have a central riser, and also makes upgrading MUCH easier also.
The first step is getting the German company that wrote the software on this to open source it. Then budding architects and engineers looking to do the numbers coudl see for themselves the viability of small scale versions.
Oh, and the last thing si that cooling a building using solar towers has been done for centuries. So its a very very smart way to design building in general.
In many projects i do, i almost always have a central tower for services and ventilation anyway, just because it makes everything else so much cheaper and easier.
Here's hoping that the NIMBY-enviro-Nazi lobby in Arizona isn't nearly as asinine as it is in California who with the backing of a U.S. senator is attempting to kill off a game-changing solar project in favor of desert tortoises. Plus, if it winds up in Arizona there will be the added benefit of getting money from California which is a fair trade for all the water they're stealing.
I can think of at least two counter examples to your statement.
Light (or any other form of electromagnetic radiation) that leaves the atmosphere without being absorbed removes energy from the system.
Any energy used to promote one form of matter to a relatively stable higher energy state form of matter (like the creation of aluminum metal) will never be released as or converted to heat within our lifetimes.
I'm sure other examples abound.
*sigh* back to work...
No, the vast majority of electricity use ends up as waste heat pretty quickly, electronics, lighting,motors, heating (obviously), cooling etc. Comparatively little is stored long term and doing that usually involves a lot of waste anyway.
Don't forget that any electromagnetic radiation that escapes the atmosphere never gets absorbed and converted to heat within the Earth's thermodynamic system. I have no idea how significant a chunk of electric power usage that represents.
*sigh* back to work...
If the glass is transparent to the wavelengths required by the solar panels, then it'll work just fine.
*sigh* back to work...
OK, I haven't seen anyone look at this yet, but I may have missed it. I just put a solar array on my house, so the idea of electrical energy from the sun is fresh in my mind. Let's look at the numbers. They are looking at 200 MW for $750 M, or at a cost of $3.75/W. In doing this, they plan to use 4 square miles, and generate under 20 W/m^2. Now that is truly pathetic?! On a sunny day, my panels produce well over 130 W/m^2, and that is AC watts, therefore taking into account all the losses in the inversion. The cost of my installation was under $7/W, and is already done...making power! Today is a crumby, cloudy, cold day yet my panels are still producing ~24 W/m^2! Why is this even being discussed as an option??? Do they think they can increase their efficiencies? It seems to me they are going to be equally dependent on solar radiation as my panels are, yet my panels are crushing them in terms of output, now, today, let alone in a few years when the solar cells efficiencies are double what my panels' are. What does SCPPA know that I am missing????
Also note that if you keep the laser aimed on one direction (and off when you can't) that you perturb the earths orbit or rotation, bringing us closer to the sun and eventually cooking all the inhabitants of earth.
Why is the post about convection modded as offtopic? Are the mods tripping on acid today?
ah, my apologies, I mis-read your earlier comment and assumed you were talking about exploiting the energy stored in the coal, not about using the sun's energy directly in place of the coal.
Man who leaps off cliff jumps to conclusion.
I use Westinghouse as an example becuase they will happily sell you a Chenobyl era reactor painted green and pretend it's new.
Name one commercial Westinghouse nuclear reactor that was built without a containment building. Just one.
Please, comparing any commercial nuclear reactor built in the West to the Soviet RBMK-1000 is a crime against logic.
Their current design, AP1000, is Gen3+, Chernobyl is considered 'early' Gen2, and that is probably an insult to all the other reactor types that fall under the Gen2 classification - its design was that bad and its implementation was, unbelievably, even worse. Hell, it was nothing more than a spiffed-up copy of an older Soviet military reactor that was designed solely for plutonium production.
even if that means buying something from outside the USA.
Ahh, so this is an anti-US rant? Well, you're in luck, Westinghouse is A-OK-Joe, since they're now owned by Toshiba, as well as having several (separate, originally independent) European subsidiaries involved in nuclear power. Nuclear power is big, but also expensive, business, thus the players went international a long time ago.
Oh wait, do you have something against the Japanese and Europeans too?
Examples are non US solutions like pebble bed, accelerated thorium and startups like Hyperion
That is just bizarre.
from: http://en.wikipedia.org/wiki/Pebble_bed_reactor
In various forms, it is currently under development by MIT, the South African company PBMR, General Atomics (U.S.), the Dutch company Romawa B.V., Adams Atomic Engines [1], Idaho National Laboratory, and the Chinese company Huaneng
I count 5 references there to US companies and universities involved Pebble Bed reactor design.
Not sure what you mean by 'accelerated' thorium but on the list of thorium reactors from http://en.wikipedia.org/wiki/Thorium_fuel_cycle, the US has been involved in that as well. The only country still actively running thorium reactors is India, and thats because, understandably, they have a *lot* of thorium and very little uranium available in their own country.
As for this: http://en.wikipedia.org/wiki/Hyperion_Power_Generation
You do realize that Hyperion is a US-based company don't you?
Reading comprehension failure there when you didn't notice "era" and built a pile of stuff on it, then for some odd reason you decided to wrap yourself in the flag and shout.
Do you really want a reply to you questioning all those words you just put in my mouth that I don't agree with anyway?
I'll only say this - all of the Westinghouse stuff will be buried by competitors that have actually done some R&D over the last thirty years or civilian nuclear will go nowhere. Some of those competitors are of course in the USA and have done more than slap on a coat of green paint and call it Gen3+.
I'm sorry you got the wrong impression there but I thought "non US solutions ... AND startups like Hyperion" got the message across. A lot of the well established US stuff is just a drain on the taxpayer but now it's possible for others to get into the market and possibly make civilian nuclear power a commercial proposition. I was also unaware that General Atomics had anything in pebble bed within a couple of decades of implementation - please cure my ignorance if you have some news (perhaps they bought out somebody else).
There's been a lot in the popular science press for a few years about accelerated thorium reactors, some call it ADS. A general page about it is here (http://everything2.com/title/thorium+reactor). That article doesn't mention India's move towards building a prototype
Very good post! And quite accurate regarding the radioactive material blowing in the wind + concentrated heavy metals in the ash.
In my view, Nat Gas turbines are another bad choice - horribly expensive fuel gotten from folks who want to kill us, and it's a polluter, just not as bad as Coal.
As to the topic of this thread...
I would really, really like to see the 10 year net MWH (Megawatt Hours) of electricity forecast from this monstrosity.
The 4 mile greenhouse is going to get dirty from sand and probably pitted from sand storms. Power plants are usually rated at peak max power.
Somebody care to check my arithmetic - I'm just pouring this out with the fat pencil.
So it puts out 200MWe at noon on a cloudless day with the sun at it's northern most point. At any other time - between 2PM and 10AM every day, and worse on all other days of the year, or if it's cloudy, this thing is going to put out a lot less net electricity. I'd give it 800MWHe from 10AM-2PM for two months a year, and 25 to 50% less the other 10 months a year. And I'd give it 8 hours more sun at an average of 80MW = 640MWH in peak months and 4 hours at 50MW = 200 MWH the other 10 months.
(800 MWH + 640 MWH) * 60 days = 85 GWH peak "summer" days
(130 MW*4 hrs + 50MW *4 hrs ) * 300 days = 216 GWH the rest of the year
So I'll throw out a 300 GWH annual total output
Let's see what a "base load" plant might put out. Their capacity factors (amount of electricity actually produced vs. what they can produce) are above 90% - 24 hours a day, every day. Yes, that includes maint and refueling shutdowns.
200MW * 24 * 365 * .9 = 1577 GWH, more than FIVE TIMES what this many square mile hipposaurus can generate.
Ooops - sorry, I failed to factor in the capacity factor on this thing. ONE generator hanging in a chimney. Yeah, that will work well - single point of failure is good. Anybody seen figures on wind generators out of service for generator bearing problems? You don't want to. Well, I'm betting this has 30% down time for the first five years and 10% for a number of years after that. It's all new pie in the sky.
Reading comprehension failure there when you didn't notice "era"
I most certainly did notice the 'era' word. Chernobyl's RBMK reactors didn't have a proper containment building. Nobody in the West has ever built a nuclear plant without one. Nobody in the West, including Westinghouse, has ever built *anything* like the RBMK-1000.
then for some odd reason you decided to wrap yourself in the flag and shout.
The odd reason in this case was that the criticism was BS.
I'm sorry you got the wrong impression there but I thought "non US solutions ... AND startups like Hyperion" got the message across.
It got the *wrong* message across. :)
Examples are non US solutions like pebble bed, accelerated thorium and startups like Hyperion
My understanding of English says that this sentence is listing 3 'non-US' solutions: (1) pebble bed, (2) thorium, (3) Hyperion. The 'and' is normally used for last item in a list like this, it does not separate the last item from the previous ones (the adjective used as the prefix to the list still applies to it). Just an FYI.
A lot of the well established US stuff is just a drain on the taxpayer
Hyperion is a private startup, the taxpayers are not involved.
I was also unaware that General Atomics had anything in pebble bed within a couple of decades of implementation
You didn't specify imminent implementations (I don't know of any), only 'solutions'. My only point was that US companies and research institutions are just as heavily involved in PBMR design/research as anyone else.
As for why there are no current implementations, have you considered the possibility that PBMR designs might have issues of their own? Perhaps it just needs a little more work before it can become viable, and that work is being done by many, including US companies/universities.
Here we go again - that's why I wrote ESTABLISHED and it's why new players that might actually do something other than just be leeches are good news. For instance the synrock project that appears to solve a lot of high grade waste storage problems could have completed 25 years ago if the big players/leeches had done more than pretend the problem did not exist.
As for "solutions" there was some work done in the US in the 1950s on pebble bed but since then as far as I know the only research money that went into it beyond that was overseas. Most of the development was done in South Africa when their paranoid nuclear weapons program (they faced no external threat they couldn't handle twice over) was redirected to something saner with purely civilian applications which has actually got them some money from China. It's still at the first full scale prototype stage now, so you are correct that there may be problems, there were many that thought fast breeders were the future before the only large one (Superphenix) started running in France in 1985 and exposed many problems with the concept. Pebble bed involves small reactors so from a safety point of view problems are not likely to be serious and from an expense point of view there is less invested in each individual reactor.
This is irrelevant. GP never said that this kind of power plant heats up the atmosphere more than it would have been if CO2 emitting methods were being used to generate the same power. GP only said that it might heat up the atmosphere, as opposed to GGP's claim that it would cool it.
Somebody pointing out heat generation in atmosphere cannot automatically be said to not have a "sense of scale".
Bingo Dictionary - Pragmatist, n. A myopic idealist.