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Self-Assembling Photovoltaic Tech From MIT
telomerewhythere writes "Michael Strano and his team at MIT have made a self-assembling and indefinitely repairable photovoltaic cell based on the principle found in chloroplasts inside plant cells. 'The system Strano's team produced is made up of seven different compounds, including the carbon nanotubes, the phospholipids, and the proteins that make up the reaction centers, which under the right conditions spontaneously assemble themselves into a light-harvesting structure that produces an electric current. Strano says he believes this sets a record for the complexity of a self-assembling system. When a surfactant is added to the mix, the seven components all come apart and form a soupy solution. Then, when the researchers removed the surfactant, the compounds spontaneously assembled once again into a perfectly formed, rejuvenated photocell.'"
Now all we need is to mimic Chlorophyll F and start capturing everything from beginning IR (720nm) on down. I'd love to see a solar cell that can respond to all of the wavelengths currently covered by terrestrial and marine plant life.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
When I skimmed the summary I thought it was gray goo time already. On closer reading, however, it appears that the molecules still need to be given a push to reassemble. The article doesn't answer the question of how much energy is needed to remove the surfactant.
The nice things about plant cells or structure is that you can grow them. In this case I can only guess that it would probably even be more efficient than to "mine" forest. Also you wouldn't need so much of it because you don't use it for its energy content, but for its energy conversion capacity. That's huge difference.
Per the article it's not nearly as biological as "plant-inspired" makes it sound.
They are using the photovoltaic effect to generate electricity on some set of proteins. Then carbon nanotubes conduct the electricity from the proteins to a common circuit. They are using phospholipids (whatever phospholipids are) along with the nanotubes to coerce proper alignment between the nanotubes and the proteins in the photovoltaic reaction sites.
The combination works pretty well (40% efficiency with sparsely populated functional structures in the solution for the prototype) until it starts to break down. The inspiration from plants is mainly that they can introduce a substance (a surfactant more specifically, although the blurb doesn't specify which) that breaks the stuff down fast, then filter the surfactant out through a membrane and the working portion self-assembles again at full efficiency.
It's this repeatable self-assembly that was biologically inspired, and it's probably necessary for high-efficiency photovoltaic solar cells since pretty much everything more efficient than silicon does break down over time. By not just accounting for the breakdown, but doing it early and often and performing a repair phase through self-assembly, it is hoped they can have high efficiency solar cells with long lifespans.
That's gleaned from TFA, which isn't much longer than what I wrote.
Now that is freaking cool technology.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
I'm reading the Diamond Age right now. Can't wait to pirate me some nanos for my daughter.
This is /., you have to say "Infringe the copyright of some nanos for my female instance".
Incredibly cool! I hope we can work towards growing solar panels soon!
That said until I see it on a website to be purchased I'm going to stick with regular solar cells.
So much of this extremely cool tech just never seems to reach the shopping cart so to speak.
"Bah!" - Dogbert
FAIL. She's not his female instance, she's a derived class.
is at http://web.mit.edu/newsoffice/2010/self-healing-solar.html
The best growing "solar panels", freely available! :)
Or maybe some vegatables in a garden?
Phospholipids are little cute guys that make up your cellular membrane (a phospholipid bi-layer). They look something like this (in as much justice as ascii can do):
o=;
They have a phosphate head (that's the round bit) with two lipid tails, one saturated fat, and one unsaturated fat.
The phosphate side is hydrophilic (it likes water) and the lipid side is hydrophobic (doesn't like water). So a whole bunch of them will collect together tail-to-tail and side-to-side to make your semi-permeable cellular membrane.
Ice 9.
xkcd is not in the sudoers file. This incident will be reported.
Eureka!
Quick infrastructure hit? Fly over the sun farm with a crop duster full of Lemon Fresh Joy.
Fantastic work, though.
It was amazing how early mine started using decorators.
Sir, your code is clearly wrong. That's what my compiler has to say about it:
phospholipid.c:1: warning: data definition has no type or storage class
phospholipid.c:1: error: expected expression before ‘;’ token
Where can I post a bug report?
And two such sheets will self-assemble into a lipid bilayer.
And just think of all the Carbon Dioxide we can use up in the process. And before you start blathering about night time when they consume Oxygen ... well duh, solar cells ... just leave the bloody light on !
Genetic analysis is not my area (I prefer structure to sequence) but I understood from a book called "Deep Time" on cladistics that it is really only informative to compare THREE species at a time, not two.
So, saying "chimps are similar to humans" is less meaningful than "chimps are more similar to humans than lemurs". All life forms on earth share some points of similarity.
Hmmm. Maybe that wasn't relevant to the question of : "Is X more evolved than Y?" but I guess I was thinking of the last common ancestor as being the third party in the comparison. That is : "Is X more evolved compared to LCA(X,Y) than Y?".
40%? that's amazing ...what are the current top picks of efficiencies at?
And now they will have patented the hell out of the technology so no-one touches it without having to pay.
Only for 20 years, which IMO is reasonable, unlike copyrights which are NOT reasonable. Giving a truly limited time monopoly does further innovation, while the virtually unlimited copyright terms do not. I'm sure it cost a lot of money to develop this tech, without the limited monopoly it would be much harder to recoup the investment.
Free Martian Whores!
I saw an episode of SG1 where they were trying to create replicating materials, and ended up with these replicators, I imagine it is along the same lines?
Sure, but it is universities in this case, which should not have to worry (much) about the money it cost. The problem I see is that I now encounter patents of fields I consider doing research in. In order not to enter legal territory, it is safer for me to research something else.
So if others do as I do, there will be a lot less research than what could have been done in 20 years if there were no patents. It isn't that patents are stopping innovation, they are just slowing it down to a glacial pace.
On top of that you have the question whether it is ethical for publicly funded universities to patent research they promised would be benefiting society when they applied for the grant.
Every experiment which ends in a big bang is a good experiment.
They are using phospholipids (whatever phospholipids are)
wikipedia is your friend.
And what is a lipid?
Free Martian Whores!
Call me when I can pick it up at Home Depot.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
if we cover the planet with solar panels, that wouldn't be good right? So there should be a limit of healthy solar energy use before messing with planet's heat balance.
Any Ideas what that should be?
The real story here is buried at the end of TFA:
The individual reactions of these new molecular structures in converting sunlight are about 40 percent efficient, or about double the efficiency of today's best commercial solar cells.
The real headine is:
Scientists Double Efficiency of Solar Cells
Every time I read a new material or new technology or gadget using nano-technology and nanotubes and such, I always wonder whether the inventors have thought of how they would dispose of the stuff so it doesn't harm the environment when it is EOL'ed. This, IMO, is a much neglected part of any news story which extols the virtues of nano-technology enabled foobar invention.
Actually, no. If you look at the color of the solar panel, you'll find its wavelength gap that it doesn't pick up light from
Actually, no. if you would look at the reflectance of a solar panel with a spectrophotometer, you'll discover that, although (for example) silicon panels do look blue, even in the blue the reflectance is very low-- about 8% or so until you get below about 250 nm, where there's just not that many photons in sunlight. It just "looks" blue, because the reflectivity in the blue, low as it is, is more than the reflectivity elsewhere in the visible spectrum.
, as that's what is being essentially reflected back to you.
You can't see the "wavelength gap where it doesn't pick up light"-- that's in the infrared, below the ability of your eyes to see. If you could see in that wavelength, though, the semiconductor would be transparent.
Most solar panels work best under green and red light, and deeper violets, IR has typically had too low of an energy potential to have any worthwhile use.
I'm not quite sure what you're talking about. Silicon cells roll off for wavelengths below about 1000 nm, which is very definitely in the infrared. (FWIW, silicon has a bandgap of about 1.1 eV-- you do the math.). High efficiency triple junction cells go considerably further into the infrared. The cell is most efficient for light very close to the bandgap-- that is, silicon cells have peak conversion efficiency around 950 nm or so.
Typical blues get pretty much ignored, which makes no sense because blue has the higher energy potential.
Blue does have higher energy per photon, but the spectrum has far fewer photons there. It doesn't get "ignored"-- in fact, most cells are quite good at converting the blue photons (they start rolling off in the near UV). However, it's not optimum to make a solar cell have peak response in the blue; there just aren't enough photons there. For a single junction cell, optimum bandgap is about 1.5 eV. For a multijunction cell, though, you do want the top cell to have good blue response.
http://www.geoffreylandis.com
I'm no expert on the matter, but I am hopeful for the tech like most geeks. From what I understand from reading articles about other work in the field and watching documentaries about it, 30% is common in the lab and even 50% or 60% is expected from some of the current work, but breakdown is rapid. The breakdown, in most cases, is caused by being exposed to sunlight and creating electricity from the exposure. Sometimes the efficiencies are down to 5% to 15% in a matter of hours or days.
Highly efficient silicon cells have been prototyped and tested up to around 40% as well. A combination solar heat engine and fuel cell of a sort has been shown on paper to work at up to 60%, but has yet to be tested even as a prototype from what I've been able to find. Some multi-junction semiconductor photovoltaics made from a small number of different alloys to widen the wavelength range are said to have the theoretical capability of 60% or even 70% over the whole solar spectrum, but the data is not yet from actual cells -- not even prototypes (it's being extrapolated from work with LEDs).
A rapid breakdown of a solar cell from exposure to solar energy is obviously bad. The main benefit as I understand it to this particular work over other developments using novel materials is that they've figured out a possible way how to deal with that problem. It works for them so far in the prototype, and hopefully it works in production systems.
The article even says they're hoping to get close to total efficiency (within the ranges of wavelengths it can use) of energy conversion with additional development. Even if they can get us a consistent range of 60-80% of a decently wide range of wavelengths my mind boggles at the applications.
Hmm.
Axe versus ironwood tree.
Axe versus punk tree.
Axe versus young poplar grove with 10,000 sub finger diameter ramets.
Axe versus grass.
Perhaps a different tool?
Third Career: Tree Farmer Second Career: Computer Geek First Career: Teacher, Outdoor Instructor, Photographer.
Perhaps we should take a another leaf out of the plant's operations manual:
Instead of making a photocell that generates electricity, make one that generates either hydrogen or methanol. Both of these can be stored for use at night.
Hydrogen is trickier to store and move around. Methanol is less efficient, and may be harder to get out of the cell.
Hmm.
Let it make a solid compound isntead, and just rebuild itself above the solid compound. Let's see. Cellulose is just a complex sugar, and has enough structural strength to support the cells.
Hmm.
If we could program it to put vessels in the cellulose, then we could supply the raw materials for creating the fuel at a single point. The cell controls it's own distribution.
Hmm.
And with suitable programming we may be able to get a single source point to spread sideways as well as up, to optimize light collection.
And if we are *really* clever the system could make a dehydrated easily stored self assembling system that all we would have to do is find a suitable site and put it in.
Damn. It's been done. Called a 'Tree'. Prior art gets me every ()&*&*( time.
Third Career: Tree Farmer Second Career: Computer Geek First Career: Teacher, Outdoor Instructor, Photographer.
a way to get a circle in out of reality.
A circle can be expressed as something at which the probability of an something else radiating from a central origin .... whatever dependant upon if you class a circle in-situ.
That may or may not screw your mind. I could elaborate on whatever, and limits are probably! required, certainly induction.
The central origin, doesn't mean that the radiant thing is singular, nor circular. The model is also dependant upon how you desire interference to be taken into account.
I also didn't put dimensions or what the radiation is etc... it's just a pointer of how it could be expressed.
But as I said in another post, models based on set theory[the theory of mathematics, less category theory I think it's called] are bound to fail. After-all it's still a theory, surely they should try to make it reality before basing reality on it!
I think some physicist said about someone's super-symmetry theory, 'anyone who knows anything about set theory......', when dismissing it.
I'm not sure if he was complaining about the guys model, or emphasising the 'theory' bit in set theory. I expect the former.
A fool and his knowledge are easily parted. (parted by being replaced with a liberal amount of brain washing!)
thank God the internet isn't a human right.