Breakthrough in development of cable for ultra-efficient electricity grid of the future


July 14, 2011

Armchair quantum wire could be used to create cables that can transmit electricity over long distances with negligible loss (Image: Beige Alert via Flickr)

Armchair quantum wire could be used to create cables that can transmit electricity over long distances with negligible loss (Image: Beige Alert via Flickr)

Image Gallery (3 images)

The United States' copper-based electric grid is estimated to leak electricity at an estimated five percent per 100 miles (161 km) of transmission. With power plants usually located far from where the electricity they produce will actually be consumed, this can add up to a lot of wasted power. A weave of metallic nanotubes known as armchair quantum wire (AQW) is seen as an ideal solution as it can carry electricity over long distances with negligible loss, but manufacturing the massive amounts of metallic single walled carbon nanotubes required for the development of this "miracle cable" has proven difficult. Now researchers have made a pivotal breakthrough that could make the development of such a cable possible.

Armchair quantum wire gets its name from the metallic single-walled carbon nanotubes (SWCN) of which it is made. These SWCNs are dubbed armchairs due to their unique shape, and while they are great at carrying current, they can't yet be made on their own. They are currently grown in batches with other kinds of nanotubes and have to be separated out - not an easy task given that a human hair is 50,000 times larger than a single nanotube.

Rice University chemist Andrew R. Barron, graduate student Alvin Orbaek and undergraduate student Andrew Owens, are carrying on work instigated by the late Rice professor, nanotechnology pioneer and Nobel laureate Richard Smalley, whose dream was of an energy efficient grid that he predicted would provide solutions to many of the world's energy problems.

Working towards this ultimate goal, the team has found a way to take small batches of individual nanotubes and make them dramatically longer. They say that ideally, long armchair nanotubes could be cut, re-seeded with catalyst and re-grown indefinitely, potentially making the development of a cable that will make an efficient electric grid of the future possible.

The technique involves chemically attaching an iron/cobalt catalyst to the ends of nanotubes and then fine-tuning the temperature and environment in which amplification could occur. Barron says refining the process has taken years but the researchers' efforts are now paying off with up to 90 percent of the nanotubes in a batch now able to be amplified to significant lengths. They say that, although the latest experiments focused on SWCNs of various chiralities (ie. they lack an internal plane of symmetry), they feel the results would be as great, and probably even better, with a batch of pristine armchairs.

According to Barron, the key was finding the right balance of temperatures, pressures, reaction times and catalyst ratios to promote growth and retard etching. While initial growth took place at 1,000 degrees Celsius, the researchers found the amplification step required lowering the temperature by 200 degrees, in addition to adjusting the chemistry to maximize the yield. Barron and his team are continuing to fine-tune their process and hope that by summer's end they can begin amplifying armchair nanotubes with the goal of making large quantities of pure metallics.

"What we're getting to is that sweet spot where most of the nanotubes grow and none of them etch," Barron said.

Orbaek hopes the team's breakthrough will eventually lead to a single furnace to grow nanotubes from scratch, cap them with new catalyst, amplify them and put out a steady stream of fiber for cables.

"What we've done is a baby step," he said. "But it verifies that, in the big picture, armchair quantum wire is technically feasible."

The Rice University research team's work is detailed in a paper published online by the American Chemical Society journal Nano Letters.

About the Author
Darren Quick Darren's love of technology started in primary school with a Nintendo Game & Watch Donkey Kong (still functioning) and a Commodore VIC 20 computer (not still functioning). In high school he upgraded to a 286 PC, and he's been following Moore's law ever since. This love of technology continued through a number of university courses and crappy jobs until 2008, when his interests found a home at Gizmag. All articles by Darren Quick

Locally produced electricity seems like a better idea than sending it for possibly hundreds of miles, with the energy loss incurred. Where does the energy leak to? The problem with nano tubes is that they are so small, that large scale production seems an impossible task. Am I right?


they need to genetically engineer bacteria to amplify these things. select for the bacteria and or yeast cells that provide ----- nanotubes in, longer nanotubes out.

longer nanotubes in, even longer ones out.

rinse and repeat. develop a cascade of species that are able to successively lengthen the nanotubes longer and longer until they are cheap to mass produce.

Facebook User

windykites1, the energy doesn\'t really \"leak\" it\'s lost because copper has resistance and anytime current passes through a resistance heat is produced and some is also converted to EM radiation. The conversion of electrical energy to heat and EM radiation accounts for most of the losses from long distance high voltage transmission.

Michael Gene

\"Locally produced electricity seems like a better idea than sending it for possibly hundreds of miles, with the energy loss incurred. Where does the energy leak to?\"

@Michael Gene. Thanks for the comprehensive answer to a question which should never have been asked on a list such as this, though it would of course be useful if every street had a power station or hydro-electric plant next to the corner shop! Maybe \'windy\' is apt?


Jeddy, in order to be able to use organisms, some organism must already have the machinery to construct nanotubes. And to my knowledge, there are none in nature. Nanotubes are unlike any biological molecule. Genetic engineering is still in the stage of \"copying and pasting\" from different organisms, and adding only some minor modifications. You could select for say, flying bacteria, but you would get none. Selection is about finding what already exists in nature (there must be variability). :)


Amory Lovins of RMI has shown in his analysis of Distributed (decentralizied) energy that multiple alternative sources are more flexible and cost efficient than the grid. The grid allows monopolies that are inherently inefficient. Ignorant, deluded, gov schooled populations also allow monopolies if gov approved and regulated, as if that fixed monopoly. It does not. In fact, a true monopoly can only exist with gov protection and is never in the public interest. It does make a few businesspersons and politicians rich at our expense. This system is called Fascism or crony Capitalism, but is the opposite of Capitalism and is often pointed out as a flaw in Capitalism and is used as a justification for more gov control. Hopefully, people will wake up someday and stop supporting their own exploitation.



locally produced electricity is not always the most A. economically friendly option B. the most ecologically friendly option C. socially friendly option.

Not all towns want to have a coal plant or a nuclear facility, or even wind or solar for that matter. People put towns in silly places that don\'t have a viable source of local energy. All in all, without a drastic change in our infrastructure, with this new cable, we can have a drastic improvement on not only our environment, but our electricity rates too :)

Johnathan Switzer

I am not sure whether the \'Wireless Transmission\' research is still on. Armchair Quantum Wire although may take some more time, could perhaps be an intermediary to the woes of transmission. Progress on solar and a solution for power evacuation could solve considerable problems to the power sector.

Asoor Shyam

ther should not be any wires on the planet .. there are other ways to conduct electricity, but they dont want to use them, they have to spend money... have a read on this link... Cheers

Tiberius Alexander
Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles