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Carbon Nanotube Towers Could Increase Solar Power
Vict0r writes "Researchers at the Georgia Tech Research Institute have recently demonstrated a way to grow carbon nanotubes in towers. The article also discusses applications for solar cells." From the article: "Reflections off the Gothamesque towers would provide more opportunity for each photon of sunlight to interact with the p/n junction of the cell. That would increase the power output from PV cells of a given size, or allow cells to be made smaller while producing the same amount of power."
We need mirrored solar cells. Just set them up so they reflect the light back and forth between all the cells for a neverending unlimited source of energy!
I Am My Own Worst Enemy
Save the galaxy!
Even though this has only been used to generate towers that are microscopic in size, let the "and I bet this can be applied to beanstalks!" threads start in 3...2..1....
... with a Beowulf cluster of these things?
Fitzghon
So where's my Space Elevator?
For soldiers operating in the field, especially in desert areas that receive lots of sunlight, the new "solar tube" cells could provide an alternate power source for the growing number of electronic devices they use
Given the amount of energy this "growing number of electronic devices" probably puts out, doesn't it make the slodiers easier to spot due to the energy signatures they are putting out? If so, doesn't it slightly impact on the actual usefulness of the electronic devices?
I'm guessing this is factored in, but how much shielding is possible, and how far would the new "solar tube" be able to be shield it's energy signature from the enemy?
"For soldiers operating in the field, especially in desert areas that receive lots of sunlight, the new "solar tube" cells could provide an alternate power source for the growing number of electronic devices they use. Without the need for trucking in fuel, compact PV cells could directly power certain applications or be used to recharge batteries in soldiers' equipment..." But, no word about innovative residential or consumer uses for the material? What about powering mobile computing systems for rural schools in India, or for use in purifying water in Africa? Sigh.
While it COULD be possible to detect solidlers using similar technology, it would still be VERY difficult.
#1 as you stated most of the electronics are probably well shielded so as no to put out much radiation.
#2 a single soldier or even a squad is a very small target from any distance and if you are close enough to really zero in then you just use your eyes.
#3 By it's very nature a photovoltaic cell will NOT put out radiation. It is built to absorb radiation, not put it out! Radio waves are produced by moving electrons back and forth quickly. A photo power cell only move electrons in one way and at a relativly low power. The photo cell will probably need NO shielding...and even if it did, most cells use visible light for power so you could shield radio waves to your hearts content and not affect the function f the device.
But that's only because we emphasize military spending, and military might. Personally, I'm of the belief that education and educational applications - such as invention, or innovative teaching and learning - in addition to practical humanitarian applications should drive technological innovation.
If we maintain the mindset that military applications drive innovation, then that's all we'll receive. On the other hand, if we start applying for grants, and applying our funding in new directions, it's forseeable that the locus of innocation could change. I, for one, strive for such.
Maybe we can power a Beowulf cluster of toaster--er, computers. Or microw--I mean, cars--dammit, GTRI, you and your confusing waffle-looking wafers! But I love'em; we should make a worldwide solar-collecting mesh covering Earth with these wafers, so anyone who needs "clean" energy can have it--using, of course, some sort of redundancy to prevent something like the 2003 Northeast Blackout. How would that go?
You can hold down the "B" button for continuous firing.
preface: my nanotech is limited to semiconductor process only.
looking at the image, the towers appear to be 20um cubes, and the tubes look incredibly uniform. That is some impressive feat to build such a tall structure!
this makes me think of 3D model creation tools that use a laser and a tank of epoxy-like goop to 'draw' a 3D prototype of a design.
can this accomplishment be extended to this technique to "render" nanodevices (er, microdevice machines), out of tubes?
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Carbon nanotubes are also all over the map these days so why not nanotubes and solar? I guess we'll have to wait a while until this becomes commercial though because I don't think carbon nanotubes can be scaled up very easily.
I mean storing solar energy from the day into a battery for the nighttime signal. Hopefully you could have guessed that, and not that a night light would be powered by a sun that's not "shining."
You can hold down the "B" button for continuous firing.
it is probably a US army grant
and they need some more money right about now
-- Avishalom is usually vish
No. If surface area mattered then leaves (nature's way of capturing solar energy) would have folds and protrusions like the gut does to increase surface area. What leaves do is make sure that some of the light gets through to the next layer. This happens both in an individual leaf - light is not caught just at the top surface but all the way through the leaf. Also a leaves don't trap all the available light, some is left for leaves below - it's totally dark walking through a forest. Make the solar cells more transparant - thats the way to get the effect of increased surface area the article referes to.
UK Laptops
If we maintain the mindset that military applications drive innovation, then that's all we'll receive.
The military is just the ultimate "early adopter" of technology. The underlying research and science is driven by educational institutions.
One of the reasons the military is such a driving force in innovation is because, like the space program, they are constantly trying to solve problems at the "extremes". Questions like "what if half the country was nuked" was one of the main reasons for the decentralized structure of the internet.
The hardest part of innovation is asking the right questions. "Necessity is the mother of invention"
D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
How hot do solar cells get? Would it be worth it to be a combined PV/water heating solar setup? I wonder if you could get useful efficiency out of the panel if it were under an inch of water and a sheet of greenhouse plastic. Barring that, I guess you could attach it to a water block, but that sounds more expensive.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
If precise formation as well as placement can be achieved, it will get over the biggest hurdle in getting into the electronics. There are still other issues (eg. contacts, surface adsorbtion etc) to be addressed though.
Nah ... the algae growing in the tank would cut down solar efficiency too much.
The higher the technology, the sharper that two-edged sword.
A simple and donated to the non-patentable public domain by me solution is:
a. get double paned glass windows
b. install on 100 story office tower
c. channel the air from inside of one window to the one above it (chaining them until top of building)
d. put wind turbines at top of building
No, all the heat energy in the PV should be going into accelerating electrons to the cathode instead. Any heat is waste, inefficiency, and powering a cooler just consumes more energy from the net. Besides, silicon solar cells get more efficient per incident watt as they heat up - a catch-22 that should be broken by making cells with a different nanoarchitecture which captures more of the incident power.
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make install -not war
And I'm sure we'll have solar as a major component of distributed power generation right after that commercial fusion plant gets built.
--grendel drago
Laws do not persuade just because they threaten. --Seneca
This is really silly. The only thing new about this is the application idea. People have been growing multiwall nanotube towers since 1998... All the new nanotube field emission displays are based on them. Single-walled towers (which this MAY be refering to, but the article is too sparse to be sure) have been around for at least 2 years, vertical SWNT published first by Maruyama in japan, followed by a much better paper (all sorts of shapes of nanotube towers, up to 2.5mm tall... yes, MILIMETERS) by Iijima -- father of nanotubes in Science, last summer).
- nanotube researcher
You are a troll, AC, but your post made me laugh out loud.
"Let a thousand flowers bloom" as my philosophy professor used to say in those matters..
You know, the reason that the military are the ones who adopt this technology and move it forward is not just because they are well funded (they are), but it is also because the military is an organization that is accountable to itself and its leadership.
If more humanist organizations had such strong and transparent chains of command, they might do well as early adopters of technology as well.
Um, is this technology not being research by Georgia Tech? Granted, they are seeking military funding, but does that make their invention somehow more evil?
If they military wanted to fund research into the production of highly nutritious high-caloric food for cheap, would you be against it because the military paid for it?
Yes, the military might use invention X for Seemingly Evil Use Y. Are you asserting that the thieving UN/random humanitarian organization is on moral high ground? Most respectable humanitarian organizations spend their budgets on operational use - they are not in the business of funding new technology. Nor would their patrons be happy about diverting funds that way. It seems to me that it is a good idea that the government is stimulating technology development through basic research, even if it is under the auspices of military funding.
Oh yeah. Solar cell should work in the infrared! Why hasn't anyone ever thought of that?
Oh wait.. they have. And it simply can't be done with the solid-state solar cell technology of today. You can't have a bandgap that small and get a current.
And yes, of course there is a lot of research going on in this.
So, what is the point of your comment? Do you mean to say that you have a solution noone knows about, or are you bitching about the state of solar cells today because you think you know something noone else does?
Generally, increasing surface area on solar cells is detrimental to producing electricity, particularly if the semiconductor material is very thin. (Yes, I am well aware that it is more than counteracted by the additional light coupled into the cell, but the writer makes it sound as though increasing surface area is a magical formula for making more power. And the increase in surface area, by itself, is still detrimental.) I would very much like to know what are the "special" semiconductor materials they plan to coat the towers with.
I don't think this is so much a breakthrough as it is just another in a long line of textured substrates for thin-film solar cells that don't even work yet and won't be hitting the market for another 10 years.
Because their cells will be more efficient, Ready believes they can use older and more mature p/n-type material technologies and less costly silicon wafers to hold down costs and rapidly advance the project into products that can be used in the field.
If he is going to use silicon wafers as simple substrates then his cells had better be substantially more efficient than standard crystalline silicon solar cells -- otherwise, he is guaranteed to be priced out of the market. Silicon wafers make up half the cost of a solar module, and the module materials and assembly make up another 30-35%. Assuming he can actually deposit these nanotowers and their semiconductor coatings at a cost similar to that of converting a silicon wafer to a silicon solar cell, it doesn't give him much choice but to leverage efficiency to get a lower cost per watt.
Nice.
I guess the quote from my professor is a little out of context. He only said that about morons who tried to argue against rationalism. He was quite the opposite of a hippie womynist.
Yeah, the military does dumbass stuff. So do most people, most of the time. I'm just saying, there is a tradition of accountability there that is stronger that most other organizations.
Note that big defense contractors are the scum of the earth, but they sub out to good guys too.
When I hear towers of nanotubes, I'm thinking of god-damn space elevators
2 microns is not exactly sky-scraping
I think he may have been pointing out that a black tube full of water is in effect a solar cell that works in the infrared.
God was my co-pilot, but then we crashed and I was forced to eat him.
...for the ultimate advance in environmentalism where we finally get to be as comfortable as we're shooting for with present tech and yet as organic as you can get: living everything. They're going in the right direction but this is very early nanotech theorizing. I'll wait for the nano-engineered biomechanical living buildings which eat all waste output from the residents, absorb ambient thermal and light energy, and are self-repairing. I'll be dead before they manage it, but it's a reassuring and hopeful dream...
If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
One of the reasons the military is such a driving force in innovation is because, like the space program, they are constantly trying to solve problems at the "extremes".
Another is that they have lots of money. I imagine if we funded the department of education the way we funded the military, we might have all sorts of research grants for building new education tools.
I imagine if we funded the department of education the way we funded the military, we might have all sorts of research grants for building new education tools.
I doubt it, while the problems for military applications are complicated, they are easy to identify. While I agree schools are under funded, what exactly innovative would you get with $40 billion more in education? Building more schools and hiring more teachers is not innovative. If you're thinking giving more money to universities to do research, that goes to the science and theory side (we'll have more thingies like carbon nanotubes we won't know what to do with), not to innovative applications.
Let's say you do fund educational research more, the military will still be the first in line to exploit it. The military would love to have more effective training techniques, improved methods of learning languages, psychological control techniques (both positive and negative), new ways to allow troops to multi-task effectiely, identification/modification of behaviors, etc.
D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
Actually, you sometimes do see solar cells mounted on heatsinks, so your idea isn't as outlandish as some would think. Generally, these cells are mounted this way only when used with an active sun tracking system and a lens concentrator in front of them (generally a fresnel) to collect more light and focus it on the cell. Since you are concentrating the light, heat becomes a real problem (think burning ants), so it needs to be dumped somehow, and this is typically accomplished via alluminum heatsinks. They tend to be passively cooled (that is, no fans or anything), but if there was enough heat to collect, might as well harness the extra energy, right?
Reason is the Path to God - Anon
Solar cells are shiny and hot. They'll be more efficient when they're black and cold. What's so wrong about mentioning that in a discussion of breakthrus in solar cell material science? In fact, what's wrong with you just answering "current tech doesn't allow bandgaps in infrared, so they waste heat"? Do you have a shiny, hot solar cell stuck up your ass or something? BTW, smartass, they're not shiny because of anything infrared, unless your species has bugeyes in addition to rectally consuming silicon.
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make install -not war
I was in DDL lab today and overheard some dude at random discussing your post on the front page of /. Congrats dude, you made it to the big leages.
N|=
As from "photon".
SIERRA TANGO FOXTROT UNIFORM
Why do they give such an exotic example of usage. Too expensive in other cases so a tradeoff with surface is made? Not usable on satellites?
I didn't see the yield with the new technology?
I thought the record was somewhere around 35%.
I can see that less surface means better portability 'in the field'.
So maybe the only market at this moment is when transportability outweighs all other factors.
> One of the reasons the military is such a driving force in innovation is
> because, like the space program, they are constantly trying to solve problems
> at the "extremes"
Another reason is the billions of dollars the US spends every year improving the ways their armed forces can kill people. It's funny - for a country so opposed to socialism and the idea of a welfare state, they certainly dish out a lot of cash to undeserving people.
All tin-foil hat wearing paranoics want to know!
This post encoded with ROT26. If you can read it, you've violated the DMCA. Handcuffs please, sergeant.
First time I've done it but this is an excellent explanation of how the world does work, even if it would be nicer if it worked the way the next parent up wanted.
No, this is Georgia Tech - they don't have Ivory Towers for research at Tech. They have Red Brick Towers. (And brick fountains, brick sidewalks, brick crosswalks, brick clyde crossings...)
This bit of nostalgia brought to you thanks to Clyde Robbins.
-Peter, who graduated from Ma Tech in 1988.
Moderation -1
40% Troll
30% Insightful
30% Overrated
Why did a simple inquiry into the obvious defects of solar cells, with specific desired improvements, generate so much opposition?
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make install -not war
Exactly what are you claiming is incorrect? Need a paper on the subject of the interlinks? How about one on the tensile strength tests? (not the same study that I saw before - they got even lower numbers, but were testing on small ropes instead of individual tubes)
In short: What exactly are you challenging?
Clean coal harnesses the awesome power of the word 'clean'.
Look at the solid-state accelerometers and gyros used in state-of-the art automotives. (Subaru's Vehicle Dynamics Control, and the similar Volvo system they plug in their ads for the XC90, etc.)
Take a guess what those solid-state accelerometers and gyros were originally created for...
retrorocket.o not found, launch anyway?
Solar cells are shiny and hot. They'll be more efficient when they're black and cold.
Not today's solar cells. What's the point in increasing IR absorption when the thermal energy isn't going to go towards increasing current?
What's so wrong about mentioning that in a discussion of breakthrus in solar cell material science?
Because your comment doesn't add anything at all to the discussion. It has no facts in it, nor is it a question, as for instance "Why aren't solar cells black and cold?".
In fact, what's wrong with you just answering "current tech doesn't allow bandgaps in infrared, so they waste heat"?
Because current tech does allow bandgaps in that range. You just can't get a current out of it, unless the thing is cooled to 1 Kelvin or so.
And what's wrong with you actually going through the trouble of Googling for an answer to why solar cells are black before announcing that they should be?
Nanotube researcher--
So can we fabricate things out of these tube structures, like that modeling I mentioned in the original post? Or are these more like tubes that carry liquids or individual atoms?
Any word on what they are good for, or is it just a milestone in nanotech???
--Someone fascinated by nanotech
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In order to conceive of a zero-carbon world which meets current per capita energy consumption for an dramatically increasing consumer base (think china with air-conditioners and hummers), We cannot take anything off the table - our buildings need to capture Solar energy at high rates of effeciency at competative rates.
Assuming energy demand to be part heat, part A/C, part light, and part electricity, we should ask first how much of that could be extracted from a 40% effecient Solar roof, and second, how can we collect the energy for market cost.
Say we use a fresnel reflection array - a spherical reflector flattened into inexpensive roof panels - then float moving "receivers" in the focal point.
It has some issues - such as astigmatism - but assuming some variation of a flat-array concentrator were possible, and the receiver could provide A/C light and electricity - that would be great - but what about the dangers?
Kid climbs on the roof to chase a ball - goes up in smoke.
So the solution lies in managing the risk with multiple arrays of a safe and smaller size, by protecting the focal zones, and ensuring a fail-safe design.
There is a lot of waste in generating solar energy far from the point of use.
If you need heat - it makes little sense to generate heat - then steam, then electricity - then heat.
So - I'm thinking that we need to find livable solar designs - and the risk is worth considering.
AIK