A brief synopsis: Having run out of energy on Earth, humanity has gone to the Moon to extract helium-3 for powering the home planet. The movie begins with shots outside of a helium-3 extraction plant on the Moon. It’s a station manned by one worker, Sam, and his artificial intelligence helper, GERTY. Sam starts hallucinating near the end of his three-year contract, and during one of these hallucinations drives his rover into a helium-3 harvester. The collision causes the cab to start losing air and we leave Sam just as he gets his helmet on. Back in the infirmary of the base station, GERTY awakens Sam and asks if he remembers the accident. Sam says no. Sam starts to get suspicious after overhearing GERTY being instructed by the station’s owners not to let Sam leave the base.

So Sam tricks GERTY into letting him go out of the station in one of the rovers. He finds the first Sam who has crashed and brings him back to nurse him to health. The new Sam decides that chronic communication difficulties—which have only permitted seeing previously recorded messages from his wife and daughter waiting for him to return back on Earth—might be an elaborate deception. He goes far enough off base to get outside of the range of jamming antennas and calls back home to Earth to discover his daughter, who was an infant in the pre-recorded messages, is now a teenager, his wife is now dead—and her father Sam is there on Earth.

The sinister truth of the helium-3 base is now fully disclosed. What is actually happening is that the “first” Sam was himself a clone (where this means everything, including all his memories, not simply a genetic clone). Evidently, the copying occurred early in Sam 1’s stay at the station. Each clone is awakened with the thought of returning home to his family in three years. What actually happens at the end of those three years is that the clone is incinerated in the return capsule, and a new clone is awakened, to begin the cycle anew.

Near the end of the film comes a striking moment. The Sam that nearly died in the earlier crash has gotten increasingly sick and will die soon. The two Sams realize that the bosses of the station are coming to kill both of them and activate a new clone. They hatch a plan that has one of them leaving back to Earth in one of the helium-3 delivery shuttles. After newly awakened Sam tells dying Sam that he deserves to go back—“you did the three years”—dying Sam disagrees, and tells new Sam that he should return to Earth, because dying Sam is too sick to make it. This is a really powerful moment in the film, and our feelings about it are helpful in untangling our own mangle of thoughts about identity and death.

Dying Sam’s sacrifice seems less significant than, say, me telling an unrelated co-worker to take the capsule home. There are suggestive biological resonances to this feeling. Think of how, in social insects like bees, individuals give up the right to reproduce in order to facilitate the genetic continuity of individuals that they are closely related to. So, would the fact that you have a copy of yourself, which diverged from you even quite some while back (in this case, three years of solitude on a Moon base), ease your anxiety about dying?

Consider the following thought experiment. Rather than three-year stints, the clones of Moon get replaced on a 24-hour cycle. You fall asleep. Your memories and any other physical changes from the “base copy” get noted and propagated to a new clone. You are then, in Moon-like fashion, vaporized, and in the morning, a new clone is awakened after these changes have been “installed.” You awake, none the wiser for this change in body. Consciousness is not continuous, of course, and discontinuities such as sleep are natural places where we can do the “body change” business with minimal mess (not unlike what was depicted in the fantastic sci-fi film Dark City). The gap between what actually happens in sleep and this scenario seems too small to quibble over. Or is it?

As experiences and other physical changes separate you from your base clone as weeks, months, and years pass, your ability to separate your own identity from that of the clone grows similarly. It is like a core scene in the play “On Ego,” when a Star Trek-like teleporter fails to vaporize the original version of the protagonist. So two protagonists now exist. From that moment forward what was once one person is now two people, with increasingly different senses of self and experiences.

Your sense of how much you would sacrifice for your copy might be a good test for how different you feel from him or her. Your sense of how much comfort you would feel in dying, knowing that this other version of you lives on, might be another good test for how much of your identity has leaked out of the lump of tissue that has hitherto conveniently been bounded off by your jacket of skin. Perhaps in the first few days after such a teleporter accident, you would feel you could give up your life for your copy (and be relaxed about the idea of dying so that one of you can go on); after a few weeks, maybe something less than your life, and after some years of passed, perhaps you’d feel you could sacrifice nothing more than you would sacrifice for a close friend. (Topic for a future movie and post: Does forming a close friendship involve blurring and merging of your two identities?)

Here’s some final thought experiments for you to puzzle over. The great anthropologist Mary Douglas wrote in her paper “The Forensic Self,”

[In] western culture, whatever we say seriously about persons and selfhood needs to some extent to be compatible with what a jury in a court of law will accept.

For a graduate degree in philosophy with Ian Hacking many years ago, I once applied this idea to the issue of multiple personality disorder (MPD), to see how the judicial system dealt with defenses of MPD. The courts have mostly taken a view most eloquently put by Judge Birdsong in the case of Georgia v. Kirkland: “…we will not begin to parcel criminal accountability out among the various inhabitants of the mind.”

Rather than MPD, let’s see where we get when we apply Douglas’ insight to the problem of multiple person disorder: having multiple copies of yourself present at once. What if, just prior to copying, one of you formed a criminal intent. Because of slightly different post-copying existences, one of you now decide to stop the other. Would it be ethical to kill your copy? What would ethics require of how you treat one another? After all, we have sometimes odd ideas of what we are allowed to do to ourselves: Yes to smoking ourselves to death, no to elective limb amputations. These confusions would only be amplified by the peculiar situation of having multiple person disorder. Or being the victim of a sinister plot by Lunar Industries on the Moon.

Their experiment has its origins back in 1871, when James Maxwell proposed a thought experiment: A demon controls the only door in a wall separating two sealed chambers filled with gas molecules. The demon allows only fast moving particles to enter one room, and only slow moving particles to enter the other room. After a while, one room has only fast moving particles, and the other has only slow moving particles. The system has lost entropy, but without expending any energy, creating a seeming violation of the second law of thermodynamics.

Leo Szilard, a Hungarian physicist, offered a key insight into Maxwell’s paradox in 1929: The demon had to expend energy measuring the speed of the molecules, thus the overall system of demon plus gas actually required work and the expenditure of energy. The demon used energy to take a measurement, creating information, preserving the second law, and establishing the idea that information could be converted to energy, and vice versa.

Proving that idea in the lab took another eight decades.

Now I’m going to confess that I’m in deep scientific waters here, probably well over my head, but this is how I understand Sano and Toyabe’s experiment: They put a series of nano-scale beads into a solution. They then put a charge on the solution that induced the beads to rotate clockwise, or at least, to consume less energy turning clockwise than turning anticlockwise. Some writers have likened this to a staircase: it costs more energy to go up stairs than down. So in this case, clockwise is downstairs.

But random molecules in the solution would occasionally strike he bead and cause it to turn anti-clockwise or go “upstairs” — building up more potential energy. The scientists (or their doctoral student-lackey) would watch the rotation carefully — whenever the ball turned anti-clockwise (go up stairs), they’d put a charge on it to prevent it from turning back (rolling down stairs), keeping it at a high potential energy. Then next time the bead randomly turned anti clockwise, they’d again prevent it from spinning back, building up yet more potential energy. In essence, they converted the knowledge of the direction of spin (information) into energy. (I actually find the diagram at top left to be more illuminating than all that clunky text, but I had to give it a go.)

The experiments were precise enough to establish a conversation rate of 28 percent, information to energy. Not really enough to solve world energy problems, but enough to prove an interesting point: Knowledge may not be exactly power, but it sure is work.

Possibly we’re to understand that these devices have their own tiny power supplies, but more likely these devices have some other way to get their juice. And wouldn’t it be nice to dispense with the problem of recharging once and for all? In our own local space-time continuum, a number of companies labor to make wireless power possible using a host of technologies, but there are two strategies that show a lot of promise, one using lasers, another using magnetic resonance.

Laser Motive,  a Seattle company, powered a small remote controlled helicopter for 12 hours, 26 minutes by keeping a laser pointed at it, a new record. It marked the second major breakthrough for Laser Motive, the first coming when it won $900,000 in  NASA’s Space Elevator Games in 2009. Laser Motive used a laser to power a climber to scoot up a 1 kilometer cable hanging from a helicopter at 3.9 meters per second (8.8 miles per hour).

At it’s most basic, Laser Motive is just using light power: On the ground it uses electricity, lenses, and mirrors to create an intense laser, which it fires at solar cells on the unmanned aircraft. The solar cells convert it back to electricity, and away they go. Using lasers allows the possibility of sending power over long distances (though always in line of sight) and for sustained periods. Laser Motive envisions unmanned aircraft going on missions, coming back and recharging from a laser without ever landing, and then returning to missions. A more far-fetched, but actively researched, application is to mount solar panels on satellites in space — where the sun comes in unadulterated by atmosphere — and beam the power down to earth.

Closer to the consumer market, WiTricity Corp. uses electromagnetic principles to wirelessly beam power from a wall outlet to a device. A device carrying a coil of wire mounted at the outlet will generate a magnetic field. A corresponding device plugs into a laptop or cell phone, also carrying a coil, but attuned to the magnetic resonance from the first device at the wall. At the outlet, electricity courses through coils in a device, producing a resonant magnetic field. The receiving device can pick up the field and electricity will be induced in its coil, and it will then send power into the laptop (or cell phone or light saber).

Neither company produces a device ready for market, nor even for mass production; there are still scientific and technological barriers to cross. But as we move beyond wired Internet and wired telephones, electricity has become the last major umbilical cord for our precious devices.  I look forward to one day dispensing with them once and for all.

Image courtesy Laser Motive

One of the major drawbacks of chemotherapy is that it damages far more of the body than just the malignant tumors it’s used to fight. In order to target just the cancerous areas, and not hit everything on the way there, researchers from the University of Texas in El Paso created a tiny solar cell. They attached model drugs to each side of the cell, one of which was positively charged, the other negatively. Once the tiny solar devices are in the body, doctors would blast the tumor with an infrared laser, causing the pholtovoltaic particles to release the drugs.

This would mean the medication would only be released at a specific location, and could be used to deliver the medical payload extremely specifically, and altering the intensity of light would control how much of the drug would be released.

At present, this work is just a proof of concept, and has a significant amount of work to go. We reported on a similar technique in November using fuzzy nanocubes.

Image of tiny photovoltaic flakes by Murat Okandan

This post originally appeared on io9.

io9. Escape to the world of tomorrow.

Below are short excerpts of the guest scientists’ responses, with links to the full versions:

Ken Caldeira: “…If you could directly produce chemical fuel from sunlight and do it affordably, that could really be a game changer…”

Jack Horner: “…If we want to see an animal like a velociraptor, we will be able to create one by genetic engineering. It might even be possible to make something that looks like a T. rex…”

Oliver Sacks: “…We thought that every part of the brain was predetermined genetically, and that was that. Now we know that enormous changes of function are possible…”

Sylvia Earle: “…We’ve explored only about 5 percent of the ocean. For us to have better maps of the moon, Mars, and Jupiter than of our own ocean floor is baffling…”

Rodney Brooks: “…The arguments we have about drugs and sports are minuscule compared with what’s coming, such as ‘What is the definition of human?’ We have the Paralympics now, but we’ll have the Augmented Olympics in the future…”

Debra Fischer: “…Every year since 1995, we have discovered more extrasolar planets than the year before. A parallel thing could happen with extraterrestrial life: After we find one example, we’ll hone our strategies to be smarter and more efficient…”

Tachi Yamada: “…I don’t believe just because you’re poor, you shouldn’t have access to lifesaving technology…”

Neil Turok: “…The science has reached the point where questions that used to be just philosophy could be observationally testable in 10 or 20 years…”

Ian Wilmut: “…We should be able to control degenerative disorders like Parkinson’s and heart disease…”

Sherry Turkle: “…Sometimes a citizenry should not ‘be good.’ You have to leave room for real dissent…”

Brian Greene: “…We may establish that there is not a unique universe—that ours is just one of many in a grand multiverse. That would be one of the most profound revolutions in thinking we have ever sustained…”

If the oceans eventually become too acidified to sustain most marine life and the jellyfish take over, we can at least take solace in the fact that we’ll have an abundant source of renewable energy. GFP (Green Fluorescent Protein), the same protein isolated in Aequorea victoria that earned three researchers the Nobel Prize in chemistry in 2008, has found a new lease of life in solar and fuel cells being developed by Zackary Chiragwandi at the Chalmers University of Technology in Sweden. Much like the dye found in cutting-edge dye-sensitized solar cells, GFP absorbs a specific wavelength of sunlight—in this case, ultraviolet light—to excite electrons that are shuttled off to an aluminum electrode to generate a current. After giving up their energy, the electrons are then returned to the GFP molecules, where they are ready for another round of stimulation (so to speak).

The cell’s design is simple: two aluminum electrodes are placed onto a thin layer of silicon dioxide, which helps to optimize light capture and energy conversion efficiency, and a single drop of GFP is deposited between them. Without prodding, the protein then self-assembles into strands to connect the electrodes and form a tiny circuit. While cheaper than conventional solar cells, dye-sensitized cells still require some costly materials and are hard to build, making these bio-inspired cells potentially a much more alluring proposition down the line. And because slightly different versions of GFP are found in a number of other marine species, there is the potential for an entire array of more finely tuned GFP cells.Chiragwandi and his colleagues also employed the same basic components to fabricate a rudimentary fuel cell. A mixture of reagents that includes magnesium and luciferase, an enzyme used for bioluminescence, produce the light that activates GFP’s electrons and help the device run—no direct sunlight needed. Because of its minuscule size and low power output, the fuel cell might be a good fit for a wide range of medical nanobots that could one day patrol our bloodstreams and treat our illnesses from within.

These devices are just the latest in a long line of renewable energy technologies that seek to bring down costs and boost efficiency by capitalizing on Mother Nature’s designs. Just a few weeks ago, 80beats’ Joe Calamia wrote about an Australian team’s discovery of chlorophyll f, a pigment that captures light in the infrared wavelength, in cyanobacteria. Since none of the current solar cells can absorb IR light, which accounts for over half of the sun’s rays, some researchers are already giddy at the prospects of harnessing this pigment for use in more efficient cells.

In the realm of science fiction, there’s also the “human” fuel cell (I almost hesitate to use the term since it inevitably brings to mind The Matrix‘s silly human batteries) being developed by a group of French scientists which Discovery News reported on several months back. This device would run on a combination of oxygen and glucose—theoretically ad infinitum—and could thus quite easily be implanted in not only humans but a variety of animals as well. Sure, it probably wouldn’t have much juice but, like the jelly-fuel cell, it could handily power those nanobots.

And if that’s all too highfalutin for you, there’ll always be the trusty poop-powered mobile.

Image: Clicksy/Flickr

The research solves a significant problem in the shift toward solar power, that of degradation. Even silicon solar panels lose efficiency over time as solar radiation breaks down its components. Yet plants don’t have this problem: they use sugar and minerals to constantly refresh their photosynthetic cells, e.g. leaves. Strano and his colleagues looked at how leaves work to develop their tiny solar generators. Using seven different chemicals the generators will self assemble, even after they’ve broken down, and with no loss of efficiency.

The basic unit requires a synthetic phospholipids, which itself is just a plate to hold the chemicals that react to light. These chemicals release electrons when photons hit them. The phospholipid plates are themselves attracted to carbon nanotoubes. The tubes, which are highly conductive, are lined up in long rows forming a wire to carry the electrons to their destination.

But even through the reaction is 40 percent efficient —- more efficient than standard thin film photovoltaic cells, which capture about 28 percent of sunlight —— that’s not even the impressive part. When the system is damaged, as sunlight is wont to do to solar panels, it will reassemble itself. Strano and his team broke down the system again and again over a 14-hour period and the system consistently put itself back together again with no loss of efficiency.

Take that Cylon Model 6. The humans will have self-assembly without your help.

(picture courtesy of PR Web)

These artificial intelligences, not likely to have had the “nostalgia module” installed, may quickly flee the home planet like a teenager trying to pretend it isn’t related to its parents. If nothing else, they will likely need to do this to find further resources such as materials and energy. Where would they want to go? Shostak speculates they may go to places where large amounts of energy can be obtained, such as near large stars or black holes.

Stephen Hawking imagines aliens covering stars with mirrors
to generate enough power for worm holes

Stephen Hawking has suggested one reason to go to high-energy regions would be to make worm holes through space-time to travel vast distances quickly. These areas are not hospitable to life as we know it, and so are not currently the target of SETI’s telescopes searching for signals of such life.

In the same article, Shostak also makes the argument that since biological intelligence is a short stepping stone to artificial intelligence, “the majority of the intelligence in the universe could well be artificial intelligence.” There’s clearly a missing premise here, which is that biological intelligence means an intelligence that invents radio or TV, or more broadly speaking, technology. But this is clearly false. From cuttlefish to corvids, the scientific evidence for high levels of intelligence in non-human animals is rapidly accumulating. At the moment, it’s not even clear that the invention of technology will be good for us as a species: an analysis of nine planetary boundaries within which human life can flourish shows that we are now transgressing three of these. Given that life has flourished for billions of years, for this to happen with just a few thousand years of agriculture and a few hundred years of industrialization shows that the step from advanced technology to artificially intelligent descendants roaming the galaxies is not one to be taken for granted.

In any event, given we can’t look everywhere, should thoughts about AI inform where we look? I don’t think so. First, based on our very limited experience, only Homo sapiens, just one of tens of millions of species of life on Earth, have developed technology. Were it not for our species, it’s unclear whether technology would ever have come about on Earth. Second, it’s far from obvious that our species will have the maturity to survive the power of our achievements for more than a blink of evolutionary time–the development of AI that leaves this planet, or at the very least serious efforts toward space colonies, is probably our best hope for long term survival–but we may not get there. Perhaps the situation is no different for other forms of life that have developed technology. They will have all emerged from a Darwinian primordial soup, a soup where certain vicious and short-sighted traits will have been essential to survival. Third, it would probably be both more successful and more scientifically useful to adjust our search strategy to improve the chances for finding extraterrestrial life, rather than intelligence.

My personal favorite for such a tweak to our search strategy is to look for places that have the hallmarks of increasing entropy. All forms of life take in energy that has some degree of entropy and re-emits it with increased entropy, such as heat. For our biosphere, we absorb sunlight and reflect heat, which appears as a “red edge” in the spectrum of reflected energy. The same, incidentally, seems likely to be true of artificial intelligence: it will require energy such as electric power, which will be radiated at higher entropy, such as the heat of integrated circuits. Sean Carroll has written an excellent explanation of the red edge in one of his postings over at Cosmic Variance. If we build better red edge detectors, we will both improve our chances of finding the much more common non-technologically savvy forms of life in the universe, and as an added side benefit, we might just detect the much rarer roaming AIs out there — although, as Hawking suggests, we may want to avoid hailing them down for coffee.

Image from Stephen Hawking’s Universe, “Fear the Aliens”

The study authors, Telma R. D. Ducati, Luis H. Simoes and Fernando Galembeck, found that tubes of aluminum, stainless steel, or chromium acquired electric charge in high relative humidity, and that the charge rose as the humidity went up.

Those metals are key, because none of them rust in swampy air, the paper said. Instead they develop a metal oxide coating that absorbs ions from surrounding water droplets. Whether the ion is OH- or H+, the other half of the water molecule ricochets off into the atmosphere, allowing the metal tube to acquire a charge.

I’m rather taken with the simplicity of Ducati et. al.’s experiment: They made a sandwich of several sheets of filter paper, a sheet of aluminum and a sheet of stainless steel. They mounted this capacitor in an aluminum box, and then put the box in a Faraday Cage. They could easily generate a charge simply by adding humidity to the space in the box, and drain it with a short circuit.

Whether this is the first step to a new kind of renewable power will take a long time to figure out, but it seems to offer a new opportunity to humid parts of the country that can’t easily benefit from wind or solar power. The scientists have decided to call it hygroelectricity, which means “humid electricity.”

I recommend the paper itself to anyone with even a modest recall of high school chemistry, or a semester of college chemistry. In most respects it’s a model of clarity not often seen in published scientific studies.

Despite what you may think, this isn’t actually such an unusual pairing. By virtue of their simple design (most only contain enough genes to encode a few dozen proteins) and infinite capacity for manipulation, viruses have become the favored go-to tool for scientists seeking to explore cellular systems and tinker with their underlying components. Gene therapists have been infecting bacterial, plant, and animal cells with viruses for years in order to shuttle in new genes and repair malfunctioning ones. In one recent application, a team of researchers led by University of Pennsylvania ophthalmologist Arthur Cideciyan restored sight to two blind individuals by injecting a virus equipped with a retinal gene into their eyes.For others, the appeal of viruses lies in their aptitude for genetic engineering. A little over a year ago, a group of MIT scientists led by Angela Belcher successfully transformed the M13 bacteriophage, a virus harmless to humans, into the cathode and anode of a lithium-ion battery. In 2006, the same team had tweaked several of the M13′s genes to make it self-assemble into a negatively-charged paper-thin film that could be used as an anode.

Constructing the cathode proved to be more of a challenge because the materials used to make it needed to be highly conducting—and most such materials tend not to be. To get around that problem, Belcher and her colleagues imbued the viruses with the ability to attract iron and phosphate along their thin, filamentous bodies and paired them up with carbon nanotubes to create dense networks of conductive material.

Unlike conventional batteries, these can be molded to fit any shape and could eventually be sprayed onto a range of other devices. The virus batteries can also be assembled in a more environmentally friendly way: at normal room temperatures and without relying on toxic chemicals. The ease with which researchers can alter their properties—to change the battery’s design or, say, to switch to a better cathode—by simply turning on or off one gene or another only makes them more attractive. This week at the American Chemical Society (ACS) meeting, Mark Allen, a postdoctoral researcher from Belcher’s lab, reported that they had done just that—engineer the virus’ genetic code slightly differently to make an iron fluoride cathode. That’s important because the use of current lithium ion battery technologies is severely limited by their relatively low energy density. Metal fluorides have shown promise because they do a better job of maximizing energy density, particularly when used in the cathode. Their Achilles’ heel is their cycle life, which is much shorter than existing batteries, but some research indicates that infusing them with oxygen could resolve that issue.

Another research group led by James Culver from the University of Maryland announced that it had also made the parts for a lithium-ion battery by using the tobacco mosaic virus (TMV), which infects tobacco plants. In a study published this month, he and his colleagues demonstrated that their virus-built silicon anode had roughly 10 times the capacity of current graphite anodes. One advantage of Culver’s design is that the batteries could eventually be grown (quite literally) in the field by farmers—though that is at least several years away. And while these batteries will initially be developed for the military to lighten soldiers’ loads on the battlefield, there is no reason why they couldn’t eventually make their way into your next shirt or pair of shoes. Perfect for when that invisible dress goes out of style.

Image: Donna Coveney/MIT

If we were ever to have a game of Survivor, the Trans-Galactic Edition, where all life forms across our local cluster of galaxies competed against each other to avoid getting voted “off the cluster,” there’d be a few attributes that might make us animals alliance-worthy. As we make worried glances toward the Stromulans from J5231, a plasma-cloud form of life with a level of consciousness far beyond our own (but alas, rather picky about what environments they will live in), we might trumpet our ability to form bodies of trillions of cells based on one single starting cell, our fantastic mobility, and the cultural productivity of our human species, which has led to amazing innovations like the George Foreman Grill.

But one of our greatest and most unsung advantages is our ability to efficiently convert the food we eat into all the energy we need to sustain our daily activities.  Take walking, for example: contemporary robots like Honda’s Asimo can use up to 30 times more energy than we do to walk. Given that in former times we spent much of our waking life walking around in search of food, we would have needed to find a whole lot more food to eat were it not for this efficiency. (Research on so-called passive walkers, which incorporates some of the energy saving tricks of human walking, has demonstrated in-the-lab efficiencies similar to humans, but are a ways off in terms of being commercialized. See link to “Cornell Ranger Robot” at the end of this post for more information).

As another example, the animal I do research on, an odd fish that hunts at night in the murky rivers of the Amazon, only needs about 4 milliwatts of power to run. That’s not a whole lot of juice–a thousand times less than an iPhone uses, and about ten thousand times less than the light you might have on if you’re reading this at night.  With that tiny bit of power it sustains not only its body and brain, but also its “electric headlamp,” an organ in its body that continually emits a weak electric field so it can sense things in the dark. We have started to unlock some of the clever tricks underlying this fish’s energy efficiency, essentially showing how it can trade off the energy it needs to move with the energy it needs to gather information.

The black ghost electric fish from the Amazon only uses 4 milliwatts of power.

Thanks to new animal-tracking techniques, we’ve recently learned about remarkable animal abilities to go long distances without so much as a nibble. As Carl Zimmer has described on sister blog The Loom, a bird called the Bar-tailed Godwit can fly 11,000 kilometers without stopping.  Eels swim from the coasts of Europe to the Sargasso sea, 6,000 kilometers away, without eating.  As for humans, not only is our walking efficient, but Daniel Leiberman has built up a strong case for the importance of exceptionally efficient long-distance running in our evolution.

Folks who build autonomous robots take note of the energy cleverness of animals, since one of the big challenges in our field is extending “autonomy time” – the time a robot can work without intervention – and currently this is constrained by its energy needs. (Robots working on The Spill are mostly powered through cables carrying electrical power from the surface and are therefore not autonomous.) My lab is working on a robotic implementation of an extremely energy-efficient fish (the Amazonian fish mentioned above). Other groups are working on robotic jellyfish, flies and bats. As efficient as these systems are becoming, they all have relatively short autonomy times because batteries need to be small or else too much energy is lost in doing the work to carry them. Instead of carrying the energy, what about eating it?

Roboticists have long dreamed of powering their devices by food to increase autonomy time. There has been some limited progress on that front. Back in 2000, Stuart Wilkinson developed “Chew Chew,” a three-meter-long train powered by sugar cubes. This was accomplished by a microbial fuel cell in which bacteria broke the food down and released electrons to charge a battery. More recent efforts include a robot out of the UK that eats flies for power–mind you it can only travel at 10 centimeters an hour, hardly fast enough to catch one.  In a different approach, water currents around underwater robots can be exploited to generate energy. Such “energy harvesting” approaches are being investigated to help power highly efficient robotic jellyfish, among other applications.

Work on microbial fuel cells has progressed slowly, however, and energy harvesting can only work in cases where there’s ambient and easily convertible energy at hand. Recent new developments on the food-to-power front may, as it were, re-energize the field. As 80beats reports, scientists have developed a transistor powered by ATP — the very fuel of your brain cells (all cells in fact). A different group has developed a fuel cell that converts glucose into electricity and implanted it in rats, generating 6.5 microwatts for sustained periods of time. While this seems an inconsequential amount of energy, pacemakers only use 10 microwatts, so such a system could have a large benefit to people who have pacemakers.

As every aspect of how we consume, produce, and–regrettably–spill energy commands our attention, our understanding of how animals convert food to fuel and the remarkable efficiency with which they use it could hardly have more relevance. While these breakthroughs can’t stanch a spill of millions of gallons of oil, they can inform new technologies that reduce our energy needs. To the consternation of dogs everywhere, we could even see a day when our robotic helpers power themselves with our leftovers.

Photograph of the black ghost knifefish Apteronotus albifrons courtesy of Per Erik Sviland

Or, start of story.

Rick Cavallaro and John Borton have built a cart that moves 2.86 times the speed of the wind, moving straight downwind. That may seem impossible, but after a year of tinkering and some financial assistance from Google and Joby Energy,  they did it. Don’t believe me? Check out the video. Keep a weather eye out for the green flag at 0:35. Notice how it’s blowing the exact opposite direction of the orange wind socks on the cart? That’s because the cart is going faster than the wind.

How is it possible?

That’s the mind bending part, and even Borton and Cavallaro admit that it’s kind of a brain twister to grasp the physics involved. But after a half hour on the phone, they managed to teach me the rudiments of what’s going on.

The key to it all is the difference between relative air speed and actual ground speed. Let’s go back to the balloon. The balloon propelled by the 10 kph wind is moving at 10 kph along the ground, but it’s relative air speed is 0 kph. It’s moving the same speed as the wind.

Ok, now bring the cart back.

The Blackbird, lined up at
New Jerusalem runway in Tracy, Calif.

The cart is quite aerodynamic, so it makes a crappy sail, but it’s still a sail. The wind gives it a push, and the car starts to roll, however slowly. As it moves along the ground, the wheels turn. At 0 kph the cart has an air speed (relative to the 10 kph wind) of -10 kph. As it gets rolling, it will catch up to the wind in velocity: at 5 kph ground speed, it has a -5 kph relative air speed, and at 10 kph ground speed, it has a relative air speed of 0 kph. At 10 kph ground speed, the cart is just like the balloon, and would not beat the balloon in a race.

But unlike the balloon, the cart has a 17-foot propeller linked by a complicated drive train to the wheels. And it’s the wheels that provide the work to turn the propeller. Remember that: The wheels turn the prop. Not the wind. Not magic pixie dust. The wheels turn the propeller. That’s important.

At 0 kph air speed, the propeller, sections of which have already been pulling on the car, really begins to bite on the air. It pulls the car forward exactly as a propeller pulls an airplane forward. The ground speed of the car increases, turning the wheels faster, which turn the propeller even faster, adding yet more acceleration. And now the whole project seems ridiculous,because everyone knows a perpetual motion machine is impossible.

But the wind never stops adding power to the system. Come back to the difference between the relative air speed and the ground speed. In the example, the cart reaches a ground speed of 10 kph, and relative air speed of 0 kph. The propeller kicks in and the cart accelerates: Ground speed rises to 20 kph, with relative air speed of 10 kph; then 30 kph ground speed with relative air speed of 20 kph, then it finally reaches a top speed of 28.6 kph, with a relative air speed of 18.6 kph (meaning, going 18.6 kph faster than the wind). There’s some loss to friction and to the drive train, but generally the wheels are always doing 10 kph-worth more work then the propeller, because the propeller is pulling through  air that’s already moving of its own accord (Cavallaro and Borton like to compare this to how a boat driving  down river moves faster than a boat in still water). That difference in work is where the extra energy enters the system, allowing the cart to move faster than the wind directly before the wind.

If that was totally baffling, don’t worry, you’re in good company. Cavallaro and Borton have worked with some of the finest minds in aerodynamics to develop the cart, and they’ve been put down as morons by other, equally fine minds. But the cart works.

The two men got into the project as an academic exercise, a kind of proof of concept with no real application. But they’ve since realized they designed and built a  device that extracts an extraordinary amount of energy from the wind, indeed, far more than any stationary wind turbine currently dotting Texas or the seas north of Germany. Borton said their cart derives 23 horsepower at top speed, roughly four times the theoretical maximum and seven times the amount of work a traditional wind turbine gets. They’ve formed a company, called Thin Air Designs, to try and tap the commercial potential of their cart.

Tapping that power will be a trick–the cart has to move, after all, and as cool as the visual would be of carts zipping along the salt flats to power Las Vegas, the high voltage power lines they’d need to transmit the power into the grid would be no joke. But it’s a fascinating application from something everyone said should be impossible.

Image and video courtesy of Thin Air Designs.

S.A.R.A.H.’s designer, Douglas Fargo, should take some cues from the Solar Decathlon, a biennial contest hosted by the U.S. Department of energy. This year, representatives from 20 teams have reconstructed their high-tech solar-powered houses on the National Mall in Washington D.C. for inspection by the public and judges alike. (See 80beats’ gallery of some of the houses.) Houses are scored on 10 criteria, from efficient appliances to market-worthiness.

Most of the houses share a few themes: They maximize the insulation to minimize heat and cool loss; they have large sections of walls that can be opened onto decks and patios to increase the amount of livable space in the house; they had ways to access appliances or climate controls remotely, whether from an iPhone app or an Internet connection; and all of them can, at the minimum, operate without electricity from the grid, though many generate excess power.

Each house has been carefully designed to suit their own regional cultures. The team from University of Louisiana, Lafayette produced BeauSoleil, a Cajun-style home that combined energy efficiency with the ability to resist hurricane-strength winds. The Illinois team’s Gable Home fits in with Midwestern farm architecture, and Team California’s Refract House is designed to take full advantage of the sunny but typically mild climate in the southern part of the state.

Team Germany‘s house is an austere cube (it is German, after all) with a single large living space on the inside, but covered in solar panels on the outside. Much like S.A.R.A.H., furniture and appliances fold in and out so the room can change function from eating space to social area to sleeping area. The house was designed to maximize the power generating possibilities, and it can pump out twice as much electricity as it needs to operate. The technology is pretty expensive, and the unit cost of the German house was projected to be between $650,000 to $850,000.

Naturally, some of the houses are a little ambitious. The University of Kentucky’s house maintains its internal environment by monitoring weather from a university feed that updates at the zip code-level resolution.  The Iowa State house has a vacuum-sealed door, which seems to me would make it challenging to open when salespeople or evangelicals come knocking unexpectedly (then again, maybe that’s not such a bad thing).

All of the houses will be on display through October 18, so Washingtonians and D.C. tourists might consider stopping by to see these would-be S.A.R.A.H.s in the, uh, flesh.

The ZPM is based on the idea of Zero Point Energy. To understand this energy, picture a pendulum swinging beneath a grandfather clock. It will eventually be robbed of its energy by air resistance and come to a stop, but in the world of quantum mechanics, a pendulum never fully stops – infinitely small oscillations will continue for eternity because that last teensy-weensy little bit of energy can never be removed. Even weirder, quantum physics tells us that ‘empty’ space is host to fields that are similarly eternally oscillating . In other words, even a vacuum has energy, and this is called Zero Point Energy.

People have been crafting devices in an attempt to tap into this energy since the first experimental evidence demonstrating its existence came about in 1957. One current leader in the field, astrophysicist Bernard Haish, got money several years ago from assorted government agencies like NASA and the Department of Defense to build one. Working with Garret Moddel of the University of Colorado at Boulder, Haish devised and patented a 2-square inch device is made of two parallel metal plates, held just a few nanometers apart, with a vacuum between them. When a gas is passed through the vacuum, any energy that’s made will be detected with a broadband photon detector. But powering futuristic cities will have to wait – the project is currently on hold for lack of further funding.

Karen Rowan

Image: Wikipedia

Turns out that—guess what?—aliens were tapping the volcano for geothermal energy. It may seem odd, on first glance, that superadvanced aliens would rely on boring old lava for a power source rather than some fancy technology, but it turns out that there is a vast amount of energy beneath our feet. Places like Iceland have been tapping geothermal energy for decades, but the U.S. is increasingly getting in on the act as well as we discussed in DISCOVER’s April issue :

If we could extract all the geothermal energy that exists underneath the United States to a depth of two miles, it would supply America’s power demands (at the current rate of usage) for the next 30,000 years. Getting at all that energy is not feasible—there are technological and economic impediments—but drawing on just 5 percent of the geothermal wealth would generate enough electricity to meet the needs of 260 million Americans. The Department of Energy’s National Renewable Energy Laboratory (NREL) asserts that reaching that 5 percent level, which would produce 260,000 megawatts of electric power and reduce our dependence on coal by one-third, is doable by 2050.