Photovoltaic Nanotech: Solar Power, Cheap(er)

"Photovoltaic Breakthroughs Brighten Outlook for Cheap Solar Power"
Scientific American (February 16, 2010)

"Novel materials might make harvesting sunlight for electricity affordable"

"Enough sunlight bathes Earth's daytime half in an hour to meet all human energy needs for a year. Sadly, there are several problems with meeting human energy demands by tapping such abundant, free solar power—not least of which is the cost of making semiconducting material that can cheaply harvest the power in sunlight. But material improvements from the California Institute of Technology and IBM might just lower the cost of solar power.

"Graduate student Michael Kelzenberg and other materials scientists at Caltech employed vertical crystals of silicon—microwires, like "blades of grass," Kelzenberg says—to capture as much as 85 percent of the full spectrum of incoming sunlight, the researchers report in the February 14 Nature Materials. (Scientific American is part of Nature Publishing Group.) Their efficiency is almost as good as that of traditional silicon wafers, yet they require just one percent of the silicon in such wafers...."

I've posted about developments at IBM before ("Solar Power Technology Gets Cheaper - IBM" (May 22, 2008))

Scientific American does a pretty good job of discussing an exciting development in solar power generation. And acknowledges something that's very important: for a technology to be used, it isn't enough to be "green." It also must

• Work
  • outside the laboratory
  • On large scales
• Be comparatively inexpensive

"Green" - And Keeping It Real

It's like those high-efficiency light bulbs that all the relevant people were using a few years ago. I'd have used them, but my household has a limited budget - and amortized cost of the things was significantly higher than the incandescent bulbs we're still using. That, and they wouldn't fit in our lighting fixtures.

Sure, it'd be nice to buy all-new lighting fixtures for the house, spend more on "green" bulbs, and - while we're at it - build a geodesic dome over the whole house, to reduce fuel bills in the winter.

But who has that kind of money?

You Mean It has to Work?!

Don't get me wrong: I think conserving power and other resources is a good idea. My family is careful about how much water and electricity we use, and we recycle. But "green" tech has to work and be affordable - not a way for rich people to congratulate themselves on being 'concerned' and 'sustainable.'

I've put more "Related posts" on this one than I usually do - because I think that working out next-generation power generation technologies is important. So important, that I think the "green" solutions should actually work.

That's because we're quite clearly at the point where we can start developing a rational alternative to burning fossil fuels: one that doesn't involve a hippie lifestyle.

Technology, Hope, and One Tough Mother

I don't think that technology will solve all our problems, of course - but I don't believe that we'll all be dead in about a month because we're around 1,000 times over Earth's 'carrying capacity' for Homo sapiens sapiens. ("Food, Agriculture, Technology, and City Folks," Drifting at the Edge of Time and Space (October 2, 2009))

If - when - technology for converting sunlight to electricity becomes efficient and affordable enough to expand its practical applications, we'll have a comparatively clean energy source. Which is good news.

There's a down side, as usual. The first paragraph starts with: "Enough sunlight bathes Earth's daytime half in an hour to meet all human energy needs for a year...." The numbers vary a bit from one telling to another, but I've heard that claim before. And, I'm inclined to believe it.

But - think about it - if sunlight is converted to electricity before it reaches the ground: it doesn't reach the ground.

I think that's one reason that Los Angeles isn't solar powered today. A couple decades back, I took best-case numbers for high-efficiency solar energy converters, and found that all electrical power needs for Los Angeles could be filled by solar power. If they paved the Mohave Desert with solar collectors, and orbited mirrors to bathe it in full sunlight 24/7/365.

Leaving the Mohave in complete, permanent darkness. The way I see it, there wouldn't be anything left alive, after the scavengers were done.

I don't see Los Angeles leaders starting that sort of a project.

And I don't think they'll have to. One option - which is finally being seriously considered - is to put the solar collectors where they belong: in orbit. (More of that in "Related posts")

No, I don't think 'we're all gonna die' not any sooner than we would normally. And I don't think humanity is doomed by our new technology, any more than we were doomed by the impending flint crisis. Again, think about it: we were using flint for quite a few tools, not all that long ago. Eventually, we'd run out of usable flint supplies - and everybody would perish. Didn't happen, because we started using something else. (Another shameless plug: "Move the Planet - or - Safety First," Drifting at the Edge of Time and Space (December 9, 2009))

And, although I think it's a good idea not to untreated dump industrial water in water we're going to drink later - I'm not all that concerned about the 'delicate' web of life on Earth.

If Mother Nature was a person, I'd depict her more along the lines of Queen Boudicca, than Clara Bow. ("Frail, Delicate Little Mother Nature?!" (December 20, 2009))

Life on Earth is around, after maybe seven major ice ages, unnumbered asteroid and comet hits, and massive volcanic events, like the one(s) that left the Deccan Traps. The Mount St. Helens was an inconvenience, compared to things like the Yellowstone eruption, about 630,000 years back.

Mother Nature? She's a tough old mother: and can take care of herself.

The Lemming will get down from the soapbox new.

Related posts:

• "Recycled House: Well, That's Cool"
  (February 6, 2010)
• "Power Stations in Space: No Panacea; But No Kidding, Either"
  (December 2, 2009)
• "Global Warming and Lost Documentation - Or, Change Happens: Deal With It"
  (December 1, 2009)
• "The Future: Just Like Today, Only Different"
  (October 24, 2009)
• "Solar Trees Top (Some) California Parking Lots"
  (August 29, 2009)
• "Techie Trellises: Really Green Buildings"
  (August 29, 2009)
• "The Unchanging Sun and Earth's Climate"
  (August 28, 2009)
• "NASA Builds Cool Green Building: Uber-Efficient and All That"
  (August 5, 2009)
• "Beach House is Energy-Efficient. Also Looks Cool"
  (August 4, 2009)
• "Passive House in France"
  (May 26, 2009)
• "Power Stations in Space: California Caught On"
  (April 20, 2009)
• " 'Monte Silo' - Cool House"
  (January 13, 2009)
• "Better ideas from England: Concept Car With Built-in Gym"
  (August 31, 2008)
• "Cobra-Head Solar Collectors Teach Students - Weird, but True"
  (May 29, 2008)
• "Solar-Powered Speedboat - No Kidding"
  (May 28, 2008)
• "Solar Power Technology Gets Cheaper - IBM"
  (May 22, 2008)
• " 'Green" Gadgets That Actually Make Sense'
  (May 7, 2008)
• "Strap-on Solar Charger for Cell Phones"
  (April 9, 2008)
• "Green Technology at Stanford: Smart Building, Smart Ideas"
  (March 5, 2008)
• "It Bends! It Cleans Itself! It's Solar Powered! Meet the Cell Phone of the Future! Maybe"
  (March 3, 2008)
• "Solar Power and the Investor"
  (February 23, 2008)
• "Nanotech Solar Collector: Revolutionary, With a Big Catch"
  (January 16, 2008)
• "Moscow's Crystal Island Project Approved"
  (January 7, 2008)

Glow-in-the-Dark Flashing Tattoos? Prosthetics With Neural Interfaces? They're Coming

"Implantable Silicon-Silk electronics could mean LED tattoos"
gizmag (November 11, 2009)


(from Rogers/Omenetto, via gizmag, used w/o permission)
"A clear silk film, about one centimeter squared, with six silicon transistors on its surface about to be implanted into a mouse (Photo: Rogers/Omenetto)"

"Tattooing dates back to at least Neolithic times and has experienced a resurgence in popularity in many parts of the world in recent years. Advancements in tattoo pigments and the refinement of tattooing equipment has seen an improvement in the quality of tattoos being produced. Today it's possible to get ink that glows under UV light, but a new technology could see tattoos that emit their own light. Researchers have been able to build thin, flexible silicon electronics on silk substrates that almost completely dissolve inside the body, paving the way for embedded LED tattoos that offer much more than just aesthetic appeal...."

It's "nanotechnology," in one sense, although the things are big enough to see: silicon transistors about a millimeter long and 250 nanometers thick. Before being implanted, they're held in place by a fine silk film, which the body later absorbs.

These days, we can pack quite a bit of circuitry on a chip a millimeter across - so in principle someone could have "EAT AT JOE'S" flashing on the back of his hand, picked out with little LED lights.

Or, more practically, a digital readout of current blood sugar levels. Hey, I might have one of these things in a few years. It would sure beat pricking my fingers a couple times a day.

Or, someone with a prosthetic arm or leg could control it more effectively, with an interface that had the person's nervous system on one side, a set of these little circuits just under - or in - the skin, and matching pickups on the prosthesis.

The American Food and Drug Administration has already approved silk for medical implants - and our bodies aren't likely to react with the gold, silicon, and titanium in the circuitry. The gizmag article doesn't mention it, but I'd think that these gadgets could get energy from our bloodstream, just like our cells do: so you wouldn't have batteries to change.

Researchers at the Beckman Institute at the University of Illinois at Champaign-Urbana, Tufts University in Medford, MA, and the University of Pennsylvania are developing this technology.

First Credit Cards and Bar Codes, Now This?! It Must be the Apocalypse!!

No, I don't think so. But I think it's likely that an odd lot of seriously freaked-out people from the weird end of the tree-huggers, Bible-thumpers, and other subcultures will be saying silly things about this sort of implant, as the news filters out.

Me? I think that, like all technology from the sharpened stick to DVDs, these implants can be misused. People aren't perfect. But I also think that gadgets like this could be very, very useful in medicine.

And for people who want to display their affection for JOE'S EATS on their hands - or foreheads.

New Rocket Fuel: Aluminum and - - - Water?!

"New Rocket Fuel Mixes Ice and Metal "
Space.com (October 21, 2009)

"Rocket propellant has barely changed in the more than 50 years since the launch of the first artificial satellite Sputnik. But a new mixture of nano-aluminum powder and frozen water could make rocket launches more environmentally friendly, and even allow spacecraft to refuel at distant locations such as the moon or Mars.

"The aluminum-ice propellant known as ALICE gets its kick from a chemical reaction between water and aluminum. Researchers hope that the hydrogen products of that reaction might go beyond launching rockets, and also feed hydrogen fuel cells for long duration space missions.

" 'In the bigger picture, we're looking at technology that can store hydrogen long term,' said Steven Son, a professor of mechanical engineering at Purdue University. 'Water is a nice, stable way to store hydrogen.'..."

Aluminum is used in rocket fuels now, because it's high ignition temperature helps shoot exhaust gasses out faster. What's new about this technology - aside from using water - is the size of the aluminum particles.

"...ALICE squeezes even more out of the aluminum by using nano-scale particles with diameters of 80 nanometers, or 500 times smaller than the width of a human hair. Such tiny particles combust more rapidly than larger particles to give an additional kick, and may allow easier control over a rocket's thrust.

" 'The nano-scale aluminum is really key to making system work,' said Timothee Pourpoint, a professor in the school of aeronautics and astronautics at Purdue. 'Using only micron-sized aluminum powder and water ice would not have worked.'..."

It's an exciting development - but far from being ready for launch vehicles.

20 Years of Building Stuff One Atom at a Time

"20 Years of Moving Atoms, One by One"
Gadget Lab, Wired (September 30, 2009)

"Sometimes genius looks like an elegant equation written in chalk on a blackboard. Sometimes it's a hodgepodge of wires, canisters and aluminum-foil-wrapped hoses, all held together by shiny bolts.

"Despite its homebrew appearance, this device, a scanning tunneling microscope, is one of the most extraordinary lab instruments of the last three decades. It can pick up individual atoms one by one and move them around to create supersmall structures, a fundamental requirement for nanotechnology.

"Twenty years ago this week, on Sept. 28, 1989, an IBM physicist, Don Eigler, became the first person to manipulate and position individual atoms. Less than two months later, he arranged 35 Xenon atoms to spell out the letters IBM. Writing those three characters took about 22 hours. Today, the process would take about 15 minutes...."

Okay: Being able to spell "IBM" with 35 xenon atoms, although cool, doesn't have all that many practical applications.

Being able to build machines, one atom at a time, at extremely small scales: That's got real possibilities.

We've got small devices now, like ViRob, an R&D prototype that's designed to tunnel through a person's body. It's small: about one by four millimeters. That's small, but certainly not microscopic.

"Nanotechnology" Doesn't Mean 'Kinda Small'

"Nanotechnology" is "the branch of engineering that deals with things smaller than 100 nanometers (especially with the manipulation of individual molecules)" (Princeton's WordNet) One nanometer is one billionth of a meter, or 0.000000001 of a meter. A millimeter, by comparison, is one thousandth of a meter, or 0.001 of a meter.

So Virob is about 1,000,000 by 4,000,000 nanometers. Yeah: That's small. But not what you could reasonably call 'nanotech.' You could measure the Queen Mary 2 in inches. (The QE2 is roughly 13,500 inches long.) But that doesn't mean it's equivalent in size to other things we measure in inches - like desktop computers.

Real nanotech, though, where machines could have individual molecules as components, has exciting possibilities beyond making really small data processing units.

So We May be Able to Build Really Small Machines: So What?

A human's red blood cell is about six to ten micrometers (AKA microns) in diameter: 0.000006 to 0.00001 meters across; or - if I'm doing the math right, 6,000 to 10,000 nanometers across. Viruses are 30 to 50 nanometers across, atoms around 0.1 to 0.3 nanometers, depending on the element. ("Size and Scale," Materials Research Science and Engineering Center / Interdisciplinary Education Group, University of Wisconsin, Madison)

They may not go into production in my lifetime - but I'm pretty sure we'll soon have machines around the size of one of our red blood cells, able to travel through our blood vessels without damaging them: programmed to look for (and maybe fix) damaged veins, arteries, and capillaries. Others could be made to swim or burrow between our cells, acting as a sort of artificial immune system.

Okay - maybe not "soon" in the American sense of the word. But I think, based on what information technology and miniaturization has done in my lifetime, the time scale is decades rather than centuries.

Related posts:

• "ViRob: Tiny 'Robot' Travels Through Body"
  (June 27, 2009)
• "Nanotechnolgy and Electronics: Atom-Sized Transistors ('Nanotronics'??)"
  (February 20, 2009)
• "Slick Idea from MIT: Nanotech Oil Spill Blotter-Upper"
  (July 10, 2008)
• "The Chembots Are Coming"
  (July 1, 2008)
• "Programmable Metallization Cell (PMC): One Terabyte of Data in a Little Package"
  (June 20, 2008)
• "Spiderman Suit: From CGI to R & D"
  (March 31, 2008)
• "Nanosieves: Energy-Efficient Filters"
  (March 5, 2008)
• "It Bends! It Cleans Itself! It's Solar Powered! Meet the Cell Phone of the Future! Maybe"
  (March 3, 2008)
• "Artificial Skin: New Technologies Coming"
  (February 12, 2008)
• "Nanotech Solar Collector: Revolutionary, With a Big Catch"
  (January 16, 2008)
• "Nanobot Designed for Clearing Arteries"
  (November 21, 2007)
• "Nanotech Batteries in Clothing"
  (October 19, 2007)
• "Something New that Water Can Do"
  (October 19, 2007)

ViRob: Tiny 'Robot' Travels Through Body

"The Tiny Robot that Can Crawl Through Your Veins—And Treat Your Tumors"
discovermagazine.com (May 26, 2009)

"The next big step in cancer treatment might be small enough to balance on a grain of salt.

"Researchers at the Israel Institute of Technology in Haifa have developed a miniature crawling robot, called ViRob, that can crawl through your lungs, find a tumor, and zap it with drugs. The bot, which is one millimeter long and four millimeters from end to end, can snake its way through the body, slipping into blood vessels and navigating through the respiratory and digestive systems..."

Judging from the photo, that would have to be a whacking great grain of salt. Just the same, ViRob is a remarkably compact device. And, at "up to nine millimeters per second," it's one fast little robot.

Today's ViRob doesn't do more than travel - and tunnel - inside a body, but eventually devices like this are, according to the article, carry cameras and tools to look around and get things done inside the body. I'll admit that I'm not entirely comfortable, thinking about a gizmo that size burrowing its way through me: but devices derived from ViRob could be lifesavers.

The article describes, sketchily, how ViRob is powered and controlled, and how next-generation devices like it may be used.

I'm quite interested in this. It's not exactly 'nanotechnology,' but ViRob looks like a step toward microscopic devices that could get medical procedures done without the sort of surgery we're used to.

Nanotechnolgy and Electronics: Atom-Sized Transistors ('Nanotronics'??)

"Scientists Make Advances On 'Nano' Electronics"
Reuters, via Wired (February 20, 2009)

"CHICAGO (Reuters) - Two U.S. teams have developed new materials that may pave the way for ever smaller, faster and more powerful electronics as current semiconductor technology begins to reach the limits of miniaturization.

"One team has made tiny transistors -- the building block of computer processors -- a fraction of the size of those used on advanced silicon chips.

"Another has made a film material capable of storing data from 250 DVDs onto a surface the size of a coin...."

I'll admit that this article is more appealing to people who like to read about "axial quadrupole nanostructures" than to those with less arcane interests.

However, if you've been following the science and technology behind the information technology we'll be using in the foreseeable future, I think you'll want to read about a team at the University of Pittsburgh and another from the Universities of Massachusetts Amherst and California Berkeley have been up to.

From the sounds of it, we're close to having computers, sensors, and memory devices with atom-sized transistors.

Slick Idea from MIT: Nanotech Oil Spill Blotter-Upper

"MIT develops a 'paper towel' for oil spills"
MIT News (May 30, 2008)

"A mat of nanowires with the touch and feel of paper could be an important new tool in the cleanup of oil and other organic pollutants, MIT researchers and colleagues report in the May 30 online issue of Nature Nanotechnology.

"The scientists say they have created a membrane that can absorb up to 20 times its weight in oil, and can be recycled many times for future use. The oil itself can also be recovered. Some 200,000 tons of oil have already been spilled at sea since the start of the decade.

" 'What we found is that we can make "paper" from an interwoven mesh of nanowires that is able to selectively absorb hydrophobic liquids--oil-like liquids--from water,' said Francesco Stellacci, an associate professor in the Department of Materials Science and Engineering and leader of the work...."

Far from the worst idea I've read about. Best of all, instead of complaining about a problem, this team did something.

The Chembots Are Coming

Update (October 20, 2009)

Related post:

• "The Chembots are Coming! It's Just Like "Terminator 2"! "
  Another War-on-Terror Blog (October 20, 2009)

---

"Futuristic Chembots Squeeze Through Small Spaces"
LiveScience (July 1, 2008)

"Soft and squishy chemical robots will one day squeeze through tight spots then expand to 10 times larger, offering an advantage over rigid robots. Once a mission is complete, a chembot would biodegrade.

"The chembots could get into a building through a crack, for example. They could explore a cave or crevice and dismantle an explosive. Or they might climb ropes, wires or trees. Another tiny idea: One chembot could pack a smaller chembot into a situation, then release it for even more minute explorations.

"Researchers at Tufts University have received a $3.3 million contract from the U.S. Defense Advanced Research Projects Agency (DARPA) to build the soft automatons...."

The article comes with a diagram, showing how a chembot would crawl and squeeze itself through a hole that's not as wide as it is.

Exciting possibilities.

The idea of chembots came from neurobiologist Barry Trimmer's studies of the nervous systems of caterpillars.

Programmable Metallization Cell (PMC): One Terabyte of Data in a Little Package

"How to fit 1TB of data on one tiny thumbdrive"
techradar.com (October 29th 2007)

"New memory better, cheaper and more efficient than flash

" Scientists at Arizona State University have created a new kind of solid state memory that they say is much cheaper and more efficient than flash. And crucially, because it uses a new kind of nanotechnology, storage capacities will be much higher than anything we have today, for a tenth of the cost.

"The new memory is called programmable metallization cell (PMC) and one terabyte (1TB) USB thumbdrives are said to be just a few years away. The largest commercially available flash drives today are only 32GB in size - 30 times smaller and very pricey...."

Very pricey now. I suspect that I may live long enough to see these things put in cereal boxes.

Spiderman Suit: From CGI to R & D

"Now it’s not just Spiderman that can scale the Empire State Building"
Institute of Physics (29 August 29, 2007)

"Physicists have found the formula for a Spiderman suit. ... Recent research concluded that van der Waals forces – the weak attraction that molecules have for each other when they are brought very close together - are responsible for creepy crawlies’ amazing sticking power."

And, as of August, 2007, another bit of research indicates that nanotubes designed to take advantage of these forces might make "Spiderman suits" practical.

Nanosieves: Energy-Efficient Filters

"Nanosieves Save Energy In Biofuel Production" Science Daily (February 13, 2008)

An energy-efficient method of separating water from other liquids. Quite impressive technology.

It Bends! It Cleans Itself! It's Solar Powered! Meet the Cell Phone of the Future! Maybe

"Morph - Nanotechnology concept cell phone" Modern Dandies (February 25th, 2008)

Photos and video.

"Nokia expects to see some of these innovations on the market into high-end products within seven years."

Artificial Skin: New Technologies Coming

"Artificial Skin Mimics the Real Thing"

"A new kind of artificial skin made from thin layers of polymers and carbon nanotubes could soon give patients and robots alike the sensation of hot, cold, and pressure."

Nanotech Solar Collector: Revolutionary, With a Big Catch

"New Solar Collector So Efficient It Works At Night Of course, there's a catch..."

Nanotechnology: an energy collector that picks up visible light and infrared. That catch is a big one, though, as the author points out: Looks like current generated by the nanoantennas is an alternating current - that oscillates ten thousand billion times a second or so. Not exactly compatible with America's 60-cycle-per-second power grid.

Still, this shows promise.

Nanobot Designed for Clearing Arteries

"Robots Get So Small They Can Fit in Arteries"

Not science fiction.

These artery-clearing nanorobots are being designed at South Korea's Chonnam National University. Their power supply supply is sugar in the patient's blood stream.

Exciting times we live in.

Nanotech Batteries in Clothing

"Weaving Batteries into Clothes / A new machine that makes nanostructured fibers could turn soldiers' uniforms into power supplies."

Tomorrow, nanotech military uniforms.

After that, button-down shirts that recharge your cell phone might be only the beginning.

Something New that Water Can Do

"Bridge of Water Spans 25mm" doesn't have any obvious practical applications. But it's cool.

Besides, this tiny bridge could turn out to be as important as the "uranium rays" that Marie Curie studied.