From Stanford University , the first carbon sequestration project that makes energy. I wonder, will Al Gore say the electricity produced by a carbon solar cell is “dirty energy”? Somewhere, off in the distance, I hear Joe Romm’s head exploding.
Stanford scientists build the first all-carbon solar cell
Stanford University scientists have built the first solar cell made entirely of carbon, a promising alternative to the expensive materials used in photovoltaic devices today.
The results are published in the Oct. 31 online edition of the journal ACS Nano.
“Carbon has the potential to deliver high performance at a low cost,” said study senior author Zhenan Bao, a professor of chemical engineering at Stanford. “To the best of our knowledge, this is the first demonstration of a working solar cell that has all of the components made of carbon. This study builds on previous work done in our lab.”
Unlike rigid silicon solar panels that adorn many rooftops, Stanford’s thin film prototype is made of carbon materials that can be coated from solution. “Perhaps in the future we can look at alternative markets where flexible carbon solar cells are coated on the surface of buildings, on windows or on cars to generate electricity,” Bao said.
The coating technique also has the potential to reduce manufacturing costs, said Stanford graduate student Michael Vosgueritchian, co-lead author of the study with postdoctoral researcher Marc Ramuz.
“Processing silicon-based solar cells requires a lot of steps,” Vosgueritchian explained. “But our entire device can be built using simple coating methods that don’t require expensive tools and machines.”
Carbon nanomaterials
The Bao group’s experimental solar cell consists of a photoactive layer, which absorbs sunlight, sandwiched between two electrodes. In a typical thin film solar cell, the electrodes are made of conductive metals and indium tin oxide (ITO). “Materials like indium are scarce and becoming more expensive as the demand for solar cells, touchscreen panels and other electronic devices grows,” Bao said. “Carbon, on the other hand, is low cost and Earth-abundant.”
For the study, Bao and her colleagues replaced the silver and ITO used in conventional electrodes with graphene – sheets of carbon that are one atom thick –and single-walled carbon nanotubes that are 10,000 times narrower than a human hair. “Carbon nanotubes have extraordinary electrical conductivity and light-absorption properties,” Bao said.
For the active layer, the scientists used material made of carbon nanotubes and “buckyballs” – soccer ball-shaped carbon molecules just one nanometer in diameter. The research team recently filed a patent for the entire device.
“Every component in our solar cell, from top to bottom, is made of carbon materials,” Vosgueritchian said. “Other groups have reported making all-carbon solar cells, but they were referring to just the active layer in the middle, not the electrodes.”
One drawback of the all-carbon prototype is that it primarily absorbs near-infrared wavelengths of light, contributing to a laboratory efficiency of less than 1 percent – much lower than commercially available solar cells. “We clearly have a long way to go on efficiency,” Bao said. “But with better materials and better processing techniques, we expect that the efficiency will go up quite dramatically.”
Improving efficiency
The Stanford team is looking at a variety of ways to improve efficiency. “Roughness can short-circuit the device and make it hard to collect the current,” Bao said. “We have to figure out how to make each layer very smooth by stacking the nanomaterials really well.”
The researchers are also experimenting with carbon nanomaterials that can absorb more light in a broader range of wavelengths, including the visible spectrum.
“Materials made of carbon are very robust,” Bao said. “They remain stable in air temperatures of nearly 1,100 degrees Fahrenheit.”
The ability of carbon solar cells to out-perform conventional devices under extreme conditions could overcome the need for greater efficiency, according to Vosgueritchian. “We believe that all-carbon solar cells could be used in extreme environments, such as at high temperatures or at high physical stress,” he said. “But obviously we want the highest efficiency possible and are working on ways to improve our device.”
“Photovoltaics will definitely be a very important source of power that we will tap into in the future,” Bao said. “We have a lot of available sunlight. We’ve got to figure out some way to use this natural resource that is given to us.”
Other authors of the study are Peng Wei of Stanford and Chenggong Wang and Yongli Gao of the University of Rochester Department of Physics and Astronomy. The research was funded by the Global Climate and Energy Project at Stanford and the Air Force Office for Scientific Research.
This article was written by Mark Shwartz of the Precourt Institute for Energy at Stanford University.
Source: http://news.stanford.edu/news/2012/october/carbon-solar-cell-103112.html
Doug Huffman says:
October 31, 2012 at 11:07 am
“The Solar Constant is still 1350 Watts per square meter above the atmosphere, equivalent to 6 – 4 kWh per square meter per 24 hours on the ground.”
For PV, a more practical number is the total yearly insolation at the surface which varies with latitude and average cloud cover. For california, that’s equivalent to about 2000 to 2500 sun hours a year, with an effective 1,000 W / m^2 at surface during full insolation; for cloudy Germany, about 800 sun hours a year.
Most oil, gas and coal is stored solar energy as a result of photosynthesis, which produces plants.
Is this just a new way to effect carbon sequestration?
Can’t fool me! It’s a toothbrush!
I wonder if the new carbon solar cell can produce more power than it took to make it.
I also wonder if it can produce more energy by catching on fire than by generating electricity
Finally, I wonder if it can produce more energy than will be required to compensate for the added heat absorbed by the Earth due to having lower albedo. One must remember that solar panels tend to have much lower albedo than land surfaces, especially like desert sand and dirt.
It’s not black.
Hmm…
All of the sun’s energy that hits the panels will be dissipated as heat somewhere, either at the panels, or in the external electric circuit. So, there will be no net cooling. Of course, if you had Maxwell’s Demon …
““Processing silicon-based solar cells requires a lot of steps,” Vosgueritchian explained. “But our entire device can be built using simple coating methods that don’t require expensive tools and machines.””
I guess they get the nanotubes and buckyballs from the local hardware store.
Rob Potter says:
October 31, 2012 at 11:07 am
““Alan Watt,
I heard carbon nanotubes run several million dollars a pound at present.”
Thanks Alan, I was going to ask if anyone knew how expensive these are. I remember when ‘bucky-balls’ were first found, they were a few ppm in middle of a lot of amorphous graphite and since then I haven’t heard much about making these compounds more efficiently.”
They have found rather efficient ways of producing them by using an electric discharge with the right parameters. Looks like a kilogram costs you 500 bucks:
http://www.arknano.com/arknano.asp?intId=10
Max Hugoson says:
October 31, 2012 at 11:04 am
Now, if we could only develope the ALL SILICON Human. (See that similarity in bonds, and the ability to homolog all C compounds with Si compounds of the same structure.)
THEN, we’d be able to tolerate -150 F to 300F temperatures. The only problem is you’d need a plasma torche to cook your Si chicken (“Yum taste like transistors Mommy!”) Unless things have changed with respect to silicon chemistry I learned some 40 years ago is incorrect, you will not be able to do it. Si-Si chains max out at around 20 or so silicon atoms if you are talking about silanes. C-C chains have (had?) no known upper bound.
View from the Solent 11:34am:
I just googled ‘buckyballs’ and top of the list was – guess what – “Buckyballs at Amazon – Low Prices on Buckyballs”. So I guess that’s where they’re getting them. 🙂
It looks interesting. I like it.
We’ve still got the issue that if someone develops something TOO neat, efficient, “too cheap to meter”, with their sights on mass-marketing, that that J P Morgans of this world withdraw their funding, and others do worse… take people out, buy up the patents, etc.
My dream is that SO MANY alternative competitive ways of manufacturing energy are going to be found, that it’s going to be like the Internet and Open Source: the big energy companies will gradually, eventually, lose out competitively to ten million different Lilliputian energy ventures.
Pay attention. Pay close attention to the sidelines, and stuff emerging from Russia. Because WUWT groupthink knocked out Rossi et al, does not mean that everything alternative is bunk. Many serious scientists are asking, what powers UFO’s? and we seem to be inching closer to understanding – inch by inch.
My local hardware store doesn’t seem to have buckyballs and carbon nano-tubes, but producing those is a lot easier than growing and processing pure silicon crystals then carefully controlling the doping pocess to turn them into semi-conductors.
The “glass” must be diamond then.
Thanks Dirk (October 31, 2012 at 11:42 am)
So, not too expensive if you just want them in a bunch. I guess the trick is to get them lined up right to perform as a semi-conductor. At least there is progress.
DirkH: “A fascinating idea is to use the carbon nanotubes to siphon off IR background radiation which surrounds us day and night with approx 150 W/m^2.”
If you ever stood outside naked in the middle of winter (or just took your gloves off) you would know there is no such thing as 150W/m^2 surrounding us day and night.
Thats just shared delusion the Moshers of the world have.
If it did become a viable and established energy source, the greens would find some reason to oppose it.
Eyal Porat says:
October 31, 2012 at 10:18 am
I have this nagging question:
If solar panels become EXTREMELY efficient, wouldn’t it be very cold near them?
At current efficiencies, the reverse is true. Solar panels have low albedo, and I bet this carbon based material has a very low albedo, close to zero. A low albedo means they absorb most of the sun’s energy and as a result its warmer near them.
If you live in a hot climate, as I do, roof albedo plays an important role in keeping houses cool. Most houses around here have reflective metal roofs with albedos above .5. Put a solar panel with an albedo near zero on the roof, and with an efficiency around 10%, and your airconditioning requirement will go up substantially more than the electricity generated by the solar panel.
Solar panels in a hot climate will increase demand for electricity.
link doesn’t go to the story
John A – What would really benefit the third world is some more coal-fired power stations. And if Barack Obama gets re-elected, US coal exports will likely increase further, making coal-fired power even more competitive for everyone else.
Lucy Skywalker said:
October 31, 2012 at 11:54 am
Many serious scientists are asking, what powers UFO’s?
———————————-
According to UFOpaedia:
“The power source of UFOs is an anti-matter reactor which uses Elerium-115 (element 115) to generate powerful gravity waves as well as other forms of energy. The conversion of matter to energy produces an incredible amount of power (E=mc2); even the tiniest amounts of Elerium produce huge amounts of power. Power Sources can be manufactured easily using Alien Alloys.
The UFO Power Source is one of the three UFO Components you must have on hand to manufacture a new ship. It is essentailly an engine, and uses Elerium-115 to propel a craft.
A UFO Power Source requires 1400 man-hours to build, $130,000, and the materials Elerium-115 and Alien Alloys. You can obtain these materials from Alien Bases and UFOs. Power Sources can be sold for $250,000.”
———————————-
All your Alien Base are belong to us!
sunshinehours1 says:
October 31, 2012 at 12:30 pm
“If you ever stood outside naked in the middle of winter (or just took your gloves off) you would know there is no such thing as 150W/m^2 surrounding us day and night.
Thats just shared delusion the Moshers of the world have.”
Well allright, it varies with the temperature. And with the emissivity of your surroundings. But let’s assume it’s 150 W/m^2 where you stand at 20 deg C or 293 K. That would mean it’s still 113 W/m^2 at 0 deg C; and 83 W/m^2 at -20 deg C.
Satisfied now?
Lucy Skywalker says:
October 31, 2012 at 11:54 am
“We’ve still got the issue that if someone develops something TOO neat, efficient, “too cheap to meter”, with their sights on mass-marketing, that that J P Morgans of this world withdraw their funding, and others do worse… take people out, buy up the patents, etc. ”
Well, the usual conspiracy assumption. Name a concrete example. The only one that is known is that JP Morgan withdrew Tesla’s funding when he found out that Tesla was researching wireless energy transmission.
Now, we have wireless energy transmission. It’s just not that efficient. There’s of course the possibility that Tesla had such an advanced idea that we are still playing catch-up but I doubt it.
Google PRIMOVE, a Bombardier project about inductive charging of vehicles.
As for buying up patents: Patents expire.
Philip Bradley says:
October 31, 2012 at 12:34 pm
I live in a hot place, and I have to say that with the current efficiency of solar panels, the best usage of them is shading the house. This lowers the temperature of the house considerably.
The total electricity of a large home panel (6X6 meters or even more) is enough only for an hour or two of air conditioning…
BTW, the questions were sarcastic, but I figure I should have added the /Sarc tag.
pyeatte says:
October 31, 2012 at 11:22 am
Most oil, gas and coal is stored solar energy as a result of photosynthesis, which produces plants.
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Still pushing the oil is dead plants meme. Abiotic oil, probably most of the gas also. See http://www.gasresources.net/
SteveT