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A sheet of graphene is a mere atom thick and has low resistance and high mobility making it optimal for both semiconductor and capacitor applications.  (Source: University of Maryland)
Graphene ultracapacitors could double the storage of existing designs thanks to breakthrough

While the continual progress of efficiencies in solar and wind seem to make these technologies ideal candidates to eventually replace fossil fuels further into the future, one key element stands in the way of their adoption.  That element is variability of the power source.  While one solution would be to offset these power sources with continuous power sources such as tidal or geothermal, another option is storage.

Currently, two primary methods exist of storing power for later use -- rechargeable batteries and ultracapacitors (other exotic methods have also been proposed).  Ultracapacitors are a growing, but not widely known field.  Ultracapacitors can be mixed with fuel cells and batteries or used independently to provide power.  While expensive, ultracapacitors have numerous advantages over batteries, including higher power capability, longer life, a wider thermal operating range, lighter, more flexible packaging and lower maintenance.

Now a new breakthrough promises even better ultracapacitors.  A typical capacitor design features two sheets with an electrolyte between them.  Charge is developed and stored on the sheets.  The key to the new research is to use graphene as the capacitor sheet material. 

Graphene is a unique carbon molecule which is a one-atom-thick planar sheet of sp2-bonded carbon atoms densely packed in a honeycomb-like lattice.  The material has exceptional surface area, among other properties.  It also is a great conductor, and thus is being explored as a material for transistors

Rod Ruoff, a University of Texas at Austin mechanical engineering professor and a physical chemist who led the research describes, "Our interest derives from the exceptional properties of these atom-thick and electrically conductive graphene sheets, because in principle all of the surface of this new carbon material can be in contact with the electrolyte.  Graphene's surface area of 2630 m2/gram (almost the area of a football field in about 1/500th of a pound of material) means that a greater number of positive or negative ions in the electrolyte can form a layer on the graphene sheets resulting in exceptional levels of stored charge."

Professor Ruoff and his team used a chemically modified graphene sheet, and several widely used commercial electrolytes.  The resulting capacitor had a charge stored per weight (called "specific capacitance") rivalling the best available traditional ultracapacitors.  And Professor Ruoff is hopeful that the material's storage can be more than doubled with tweaking.  He states, "There are reasons to think that the ability to store electrical charge can be about double that of current commercially used materials. We are working to see if that prediction will be borne out in the laboratory."

His current team consists of graduate student Meryl Stoller and postdoctoral fellows Sungjin Park, Yanwu Zhu and Jinho An, all from the Mechanical Engineering Department and the Texas Materials Institute at the university.

Their impressive findings are reported in the forthcoming Oct. 8 edition of Nano Letters.

The U.S. Department of Energy has said advancing storage technologies is one of the most pressing needs of the renewable resource industry.  Other fields such as electric cars could also benefit from the research.  A graphene ultracapacitor equipped next-generation version of the Chevy Volt could get twice the range on a single charge or cut the battery weight in half.  It could even extend the life of laptop batteries.

Resources and funding for the project were provided by the Texas Nanotechnology Research Superiority Initiative, The University of Texas at Austin and a Korea Research Foundation Grant for fellowship support for Dr. Park.



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Experiment
By uhgotnegum on 9/17/2008 1:55:34 PM , Rating: 5
I propose an experiment to Mick and Asher, and it goes like this...

You both tend to write on similar topics (e.g., environmental issues that have political implications), is that fair to say? Assuming you both said, "yes," I would be interested in you both writing articles on the same exact item, both to be submitted at the same time and both written without any "consulting" of the other.

In total, my idea is each of you would write two articles, one subject matter proposed by Mick, which you both would write on, and the other proposed by Masher (i.e., Mick may have suggested this article's breakthrough and both of you would then write on it).

What do you guys say?

To sum up:
Two articles, one each, on a topic Mick chooses
Two articles, one each, on a topic Masher chooses

Purely interested in seeing how you both would tackle an issue if given the same time, information, etc. Thanks for the consideration.




RE: Experiment
By JasonMick (blog) on 9/17/2008 1:59:47 PM , Rating: 2
I'm game. :)


RE: Experiment
By Mitch101 on 9/17/2008 2:16:10 PM , Rating: 5
The Atari 2600 Game Spy vs Spy keeps popping into my head.


RE: Experiment
By nah on 9/17/2008 3:49:28 PM , Rating: 2
Jason : Solar,Wind,Solar,Wind

Michael : Nuclear, Oil, Nuclear, Oil

nah : what, me worry ?


RE: Experiment
By BansheeX on 9/18/2008 9:41:19 AM , Rating: 3
Mick doesn't seem to understand that there is no benefit to solar or wind over fission for major generation applications. They need vast amounts of real estate, they're much more costly to build and maintain per watt produced, wind is less safe to workers, they're not less harmful to the environment, and they can't produce power under any conditions. I like wind for rural areas, but Mick gives it disproportionate attention and revolutionary flair. There's no way in hell this stuff should become more than 10% of our national power generation.


RE: Experiment
By alcalde on 9/18/08, Rating: 0
RE: Experiment
By masher2 (blog) on 9/18/2008 11:34:40 PM , Rating: 4
Wind turbines do, however, have enormous spinning blades and weighty poles, both of which can most certainly kill you, especially in areas exposed to high winds-- which, coincidentally, is where such windmills tend to be built.

In fact, despite the small amount of power generated by wind at present, several people have already died from such accidents. How many have died from nuclear waste in the Western world? None whatsoever...in a half-century of operation.

So much for that theory.

Wind also requires the mining and production of vast amounts of steel and concrete, far more than nuclear reactors require...operations which have a number of toxic byproducts.

> "Oh, and then there's the drilling for fuel."

What drilling? We have enough fuel from spare nuclear weapons alone to power the nation for more than 200 years-- all without mining an additional ounce of uranium. And even after that, nuclear requires far less mining that wind power, due to the vastly smaller amount of resources it requires.

> "the non-renewableness of nuclear."

There's enough nuclear fuel on earth to last several times all of recorded human history. On that basis, nuclear is just as renewable as solar or wind. All three will run out eventually...but it's a problem so far in the future, we can't even conceive of it.

> "we don't have to worry about solar or wind falling into the hands of terrorists."

What would terrorists do with nuclear fuel? They certainly can't make a nuclear bomb out of low-enriched uranium. The plutonium generated is poisoned with so much Pu-240 that it's essentially useless as a nuclear weapon...and even refining it out is so complex and requires so much resources that one might just as well build your own reactor or enrichment plant (which is why nations like Iran, Pakistan, and North Korea chose just that route).

So that leaves a "dirty bomb" -- something more useful for generating irrational fear than any real damage. But if one wants radioactive material for such a bomb, it's much easier to get it from sources like medical radionuclides or even a large amount of discarded smoke detectors. Or -- if you're a smart terrorist -- you skip the idea entirely, and get something truly destructive, like a biological agent, or some much-more-deadly sarin, ricin, or other toxins.


RE: Experiment
By lco45 on 9/23/2008 3:53:35 AM , Rating: 2
Yes, but to be fair Masher, even if a whole field of wind generators failed at the same time it wouldn't render the entire region unlivable for hundreds of years, like Chernobyl did.
Having said that, fission is an excellent choice for power generation, and is orders of magnitude safer than mining for coal, or warring for oil control.


RE: Experiment
By Regs on 9/23/2008 10:55:32 AM , Rating: 2
You know what ticks me off?

The Sun goes away each day and doesn't let us know where it's going.

How can we work with this? Gawd damnit.


RE: Experiment
By Etsp on 9/17/2008 2:44:34 PM , Rating: 2
I'd actually also like a third article chosen by the DT master himself, Kristopher Kubicki Just to make sure there is at least one neutral party involved. :)


RE: Experiment
By Lord 666 on 9/17/2008 3:40:18 PM , Rating: 2
Ideally, Kris would be included as a writer in all three assignments.

Masher topic - all three write
Mick topic - all three write
Kris topic - all three write


RE: Experiment
By masher2 (blog) on 9/17/2008 4:07:26 PM , Rating: 2
That's 9 papers already. I think people would lose interest long before they reached the end.


RE: Experiment
By danrien on 9/17/2008 5:30:51 PM , Rating: 3
I would actually be interested in seeing this all the time. Sort of like Hannity and Colmes, but without the cherry-picked idiot Colmes that Fox picked to beat up (I honestly pictured a Fox executive finding a homeless bum off the street, and telling him to spew unintelligible shit for a job as long as he went by the name 'Colmes').


RE: Experiment
By TSS on 9/17/2008 6:25:18 PM , Rating: 2
on a regular basis, yes, but for once it would be fun to see the results.

which would probably be anything but non-biased objective journalism. however, that would fit perfectly with most if not all other media outlets.


RE: Experiment
By Lord 666 on 9/17/2008 6:32:32 PM , Rating: 3
Done on a limited basis (once a month, maybe just once) there might be some interest if positioned as a "contest."

To be fair, the author names should be ommitted, but due to the distinct writing styles, the author will be easily identifiable.

One open aspect would be how to grade feedback and author responses to such feedback. A factual piece should be able to stand on its own, but in a collaborative Web 2.0 world, author responses to feedback is always a good thing


RE: Experiment
By johnsonx on 9/17/2008 11:10:53 PM , Rating: 3
I would say Kris doesn't need to write for this purpose, but having him pick one topic is a good idea.

Also, spread it out over a few weeks; we don't need 3 pairs of articles all at once.


RE: Experiment
By therealnickdanger on 9/17/2008 2:50:23 PM , Rating: 2
I suggested this same thing some time ago... Slipped through the cracks of teh interweb, I think. :P

It would be a very interesting exchange. It would essentially be the same as it is now, just better organized and promoted.

C'mon Kris, you know it's a good idea!


RE: Experiment
By uhgotnegum on 9/17/2008 3:44:10 PM , Rating: 2
i'm n ur idea,
stealn' all ur raetingz

maybe should each write the suggestion, post it at the same time, and see how they differ...or that might just be a joke ;)

(didn't mean to steal your thunder)


RE: Experiment
By SeanMI on 9/17/2008 2:51:21 PM , Rating: 2
I can't rate him up any higher so I figured I'd throw my 2 cents in and let you know I'd like to see this happen as well :)


RE: Experiment
By MarcLeFou on 9/17/2008 7:07:23 PM , Rating: 2
I also think this would be a good idea - if only to get both side of the coin. Opposing viewpoints often leave one better informed on the topic at hand.


RE: Experiment
By jlips6 on 9/17/2008 11:50:22 PM , Rating: 3
I would also be content with a dance-off.


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