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Thursday, July 23, 2009
A novel approach to extract energy from flowing water currents. It is unlike any other ocean energy or low-head hydropower concept. VIVACE is based on the extensively studied phenomenon of Vortex Induced Vibrations (VIV), which was first observed 500 years ago by Leonardo DaVinci in the form of “Aeolian Tones.” For decades, engineers have been trying to prevent VIV from damaging offshore equipment and structures. By maximizing and exploiting VIV rather than spoiling and preventing it, VIVACE takes this ‘problem’ and transforms it into a valuable resource for mankind. Vortex Induced Vibrations (VIV) result from vortices forming and shedding on the downstream side of a bluff body in a current. Vortex shedding alternates from one side to the other, thereby creating a vibration or oscillation. The VIV phenomenon is non-linear, which means it can produce useful energy at high efficiency over a wide range of current speeds. Vortex Induced Vibrations Oscillates Objects in Fluid Currents Vortex Induced Vibrations Oscillates Objects in Fluid Currents. VIVACE devices have many potential advantages, which improve installation survivability in the hostile underwater environment and enable low-cost power production by decreasing capital cost and minimizing maintenance. * High energy density – permits low cost energy to be produced from relatively small installations – requiring up to 50 times less ocean acreage than wave power concepts. * Simple and rugged moving parts – allows for robust designs that can operate for long periods in the underwater environment with minimal maintenance. * Low dependence on ocean/river conditions – application of non-linear resonance permits useful energy to be extracted over a wide range of current speeds. VIVACE and other renewable energy technologies also face regulatory hurdles. Again, VIVACE is advantaged by salient benefits over other technologies. * Non-obtrusiveness – installations can be positioned beneath the surface, thereby avoiding interference with other uses, such as fishing, shipping and tourism. * Compatibility with marine life – VIVACE utilizes vortex formation and shedding, which is the same mechanism fish use to propel themselves through the water. Prototype, funded by the U.S. Department of Energy and the Office Naval Research, is currently operating in the Marine Hydrodynamics Laboratory at the University of Michigan. This device has met and often exceeded expectations; thereby, providing strong evidence to proceed to the next scale, a multi-kilowatt field demonstration.
The Red Badge of Climate Change Tracing the flow of a blood-red Fluorescent dye may reveal the ultimate fate of the Greenland’s ice.
From the June 2009 issue, published online May 18, 2009
THE MOMENT: Ian Bartholomew, a geoscience doctoral researcher at the University of Edinburgh, pours fluorescent dye into waters beside Russell Glacier in western Greenland. Downstream, he and his colleagues will test the water with a fluorometer, which can detect the dye even at weak concentrations. From those readings, researchers can calculate the volume of meltwater coming from the glacier. Bartholomew is using the data to determine whether seasonal meltwater is accelerating the movement of the Greenland ice sheet by seeping through cracks and lubricating its base. Until recently, scientists had believed Greenland’s ice was too thick for meltwater to penetrate.
THE SHOT: Photograph by Ashley Cooper using a Canon EOS 5D with a 21-mm lens, ISO 100, f/9, 1/60 second.
Source: http://discovermagazine.com/2009/jun/18-red-badge-of-climate-change
Glass that “breathes” like gills, solar cells that imitate leaves, and other biomimetic technologies
by Blaine Brownell
From the March 2009 issue, published online March 2, 2009
Image courtesy of Shimzu
Want to cool a building? Steal a trick from the forest canopy and use leaves for shade, as Osaka University did with its Frontier Research Center (pictured above). Builders, architects, and designers seeking better ways to go green are increasingly turning to nature—the original green—for solutions that have proven track records in the real world.
Engineering inspired by nature can be “functionally indistinguishable from the elegant designs we see in the natural world,” says Janine Benyus, a leading proponent of nature-based design and founder of the Biomimicry Institute. Benyus says the strategy has already yielded a wide range of new products that may replicate nature’s successes: ceramics with the strength and toughness of abalone shells, self-assembling computer chips that form by processes similar to the way that tooth enamel grows, adhesives that mimic the glue that mussels use to anchor themselves in place, and self-cleaning plastics based on the structure of a lotus leaf.
Some biomimicry efforts are tackling large-scale challenges such as supplying energy to an entire building. The Kyoto-based company Kyosemi has developed a power-harvesting solar cell that imitates the way that trees collect sunlight from various angles with their leaves. Called Sphelar, the product comprises little spherical cells that can be incorporated into a building’s windows. Unlike standard photovoltaic panels, Sphelar can absorb light from many directions, providing more consistent power generation as the sun moves across the sky.
Other projects aim to keep sites safer and cleaner. Kinetic Glass can alert workers or residents to dangerous conditions. Under development by the creative think tank The Living, this new product takes a cue from animal respiratory systems. The glass is made with a slit silicone surface that allows air to pass through, and it has tiny sensors that can detect the levels of certain gases. In the presence of, say, excess carbon dioxide, the material opens and closes its “gills” to exchange the air. The gills’ movement also acts as a visual warning to building occupants.
“As all kinds of sensors become smaller, cheaper, and more networked, there is a great opportunity for architecture to come to life and respond to information about environmental conditions that are normally invisible,” says David Benjamin, an architect with the design team at The Living.
Inspired by the air- and soil-purifying abilities of plants and fungi, other scientists are developing materials that can help eliminate harmful substances in their immediate vicinity. Concrete that absorbs carbon dioxide, highway barriers that break down smog, and paint that eliminates odors in the room where it is used are just a few of the products that these researchers are working on.
The SuperAbsorber highway barrier, for instance, reduces local airborne pollution through a process known as photocatalyzation. Architects Douglas Hecker and Martha Skinner of the design studio Fieldoffice dreamed up SuperAbsorber as they discussed how “barriers should be designed to absorb airborne pollution and light pollution, in addition to sound pollution,” Hecker says. According to Italcementi, an Italian maker of photocatalytic cement, the airborne pollution of a large city could be cut in half if pollution-reducing cement were to cover just 15 percent of urban surfaces.
BuzzWords
BIOMIMICRY The emulation of natural designs and processes; imitation of life
SELF-CLEANING PLASTIC Plastic with a surface that causes liquids to roll off, achieved by forming it in a mold with tiny bumps like those on the surface of a lotus leaf
PHOTOVOLTAIC Made of solar cells that can convert sunlight directly into electricity
PHOTO-CATALYZATION A process that uses light to speed up chemical reactions, such as the breakdown of pollutants
Source: http://discovermagazine.com/2009/mar/28-sustainable-architecture-takes-cues-from-original-green-nature
Just two months ago, we reported that the federal government’s hydrogen car program was going down like the Hindenburg, as the Department of Energy announced that it would slash research funding. At the time, Energy Secretary Steven Chu said that after years of research, hydrogen-fueled cars were still years away from commercial viability. “We asked ourselves, ‘Is it likely in the next 10 or 15, 20 years that we will convert to a hydrogen car economy?’ The answer, we felt, was ‘no,’” Chu said in May [CNET].
But the program has proven harder to take down than the flammable zeppelin: Both houses of Congress seem inclined to restore funding. The House of Representatives voted on an energy package on Friday that includes $153 million for hydrogen and fuel cell research, and the parallel bill that will go before the Senate currently includes $190 million for the program.
The Department of Energy’s decision to cut funding had distressed car companies working on hydrogen car prototypes, and also discomfited California legislators, who had been expecting further federal help for a state-wide hydrogen initiative. Now the lobbying of those interest groups appears to have paid off. “We’re encouraged,” said Patrick Serfass, a spokesman for the National Hydrogen Association. “Congress has shown that it is very well educated about these technologies. It sees the benefits of hydrogen and fuel cells, and understands we need to pursue a portfolio of technologies, not just one or two. Frankly, it’s too early to choose” [The New York Times, blog].
Related Content:
80beats: Hydrogen Car Goes Down Like the Hindenburg: DoE Kills the Program
80beats: The Super-Small, Open-Source, Ultracapacitor-Using Hydrogen Car
80beats: Carbon Nanotubes Could Replace Platinum and Lead to Affordable Hydrogen Cars
DISCOVER: Under the Hood of the First Real Fuel-Cell Car
DISCOVER: Future Tech test drives three hydrogen cars
DISCOVER: Lovin’ Hydrogen describes Amory Lovins’s vision of a hydrogen-powered future
Image: flickr / ideowl
- 1. robot makes music Says:
July 22nd, 2009 at 4:07 pmElectric vehicles are ready to go.
Yet we’re wasting all our money on something that may never help us.
Not only that, but you need electricity to split hydrogen from fresh water – a resource we are quickly running out of – so why go through all that trouble when you can just put the electricity directly into a car and make it go that way?
Instead, we’re converting the electricity (at a loss) to hydrogen (which is still dangerous, explosion wise – no, the Hindenburg didn’t light up from the hydrogen, it was the magnesium – but the hydrogen wasn’t compressed, either – compressed hydrogen won’t make anything buoyant) to reconvert to electricity (at a loss) to run the car.
The only thing hydrogen will do is ensure there is a transportation and control structure involved with the distribution chain – the more middlemen, the more beaks get wet, the more tax gets applied, the more the rich benefit.
- 2. jjpro Says:
July 23rd, 2009 at 10:09 amHey “Robot”, please get your facts correct before you blog. Hydrogen fuel-cell cars ARE electric. The automobile manufacturers will tell you that more work needs to be done for pure-battery electric vehicle to become viable in the marketplace. Hydrogen energy systems use LESS water than current fossil-fuel systems running our powerplants. Hydrogen is relatively safer than gasoline, and it could be argued, safer than LI-Ion batteries. Hydrogen systems are just as efficient as pure-electrical-battery systems. And, hydrogen can be made right at your home and with many feedstocks, ensuring our energy independence and security, and decreasing any stronghold over its distribution.
Why do you think hydrogen is the fuel of choice for NASA? And, Discovery, hydrogen did not cause the Hindenburg disaster; I refer you to Dr. Addison Bain’s (former NASA engineer) research on the matter.
Congress is right to restore funding. Hydrogen should get much more money, not less.
- 3. wjv Says:
July 23rd, 2009 at 10:30 amrobot makes music @1: I second your sentiment. You’re absolutely right.
@jjpro: I am very skeptical that the hydrogen scheme is just as efficient as the conventional electrical car scheme. If you could refer me to some sort of reference for that claim, that’d be great. Cuz just thinking about it, I wouldn’t come to that conclusion. Consider the energy end-game where we get something like 90% or so of our energy from wind, solar, geothermal, hydro. Battery/Capacitor electric cars would recharge from the grid supposedly so they’re only energy losses come from electrical transmission loss (depends on distance but something like 15% I think is typical) and then the electric motor loss which is very small ~5%.I could even throw in battery idling discharge of 10% say. Compared to hydrogen which requires the same transmission loss, and the electrolysis, which if I remember correctly is 75% efficient on a good day. and then a hydrogen fuel cell is 70% efficient for best models. Also, I’m not sure if people quantify the amount of hydrogen lost from diffusion out of the storage tank but I bet it’s at least as much as the battery idling discharge. (Hydrogen is hard to contain, being so small)
So it seems the electric battery car has a pretty major efficiency advantage in this comparison. I’m I overlooking something, jjpro, or did you?
I guess we will see (and i think you can be fairly confident) that an economic scheme involving hydrogen as a fuel will never be able to compete with a smaller transmission loss scheme like electric cars (with batteries/capacitors). Especially if the news about EEStor’s ultra-capacitors is even half true.
- 4. wjv Says:
July 23rd, 2009 at 11:07 amsorry double post edit
- 5. Art Says:
July 23rd, 2009 at 11:55 am@jjpro
Where in the article did the author give the cause of the Hindenburg? I saw the simile but it doesn’t imply the author is ignorant as to the cause of the Hindenburg disaster.
I guess you should be the one writing for a magazine, but you’re tragically stuck commenting on other people’s work and being snarky about it at the same time. I would venture to guess that Eliza Strickland knows as much or more about hydrogen as you. You also felt the need to tell robot to get his facts straight, only to fill your quip with “something like”, “~”, “if I remember correctly” and “I’m not sure”. Remarkable!
Thanks for not going through the trouble of substantiating your claims with some facts instead of fuzzy statistics. Really informative. - 6. Chemgirl Says:
July 23rd, 2009 at 12:43 pmHave you noticed how strongly the hydrogen car debate affects people? My husband and me have actually stopped discussing it, since we’re of different sides on that debate. Peace.
- 7. darth malicus Says:
July 23rd, 2009 at 1:47 pmrobot makes music is right, it takes a substantial amount of energy to separate hydrogen from water, more so than you can get out of the hydrogen itself, making a need for hydrogen refueling stations, also, hydrogen seeps through porous metals at a very high rate, if you fueled up your car with hydrogen you probably will have a week to use it before it is all gone, same with refueling stations and the infrastructure they will all have leaks it would take trillions of dollars to implement the infrastructure and take more electricity than we use now to create the hydrogen when you add it all up, it adds to a loss a tough pill to swallow i know, and environmentalists need to put a stop to coal and fossil fuel burning power plants and switching to nuclear before we even think about using hydrogen. and another thing, automobiles are tough environments for any kind of system, and the slightest malfunction or leak can be very catastrophic with hydrogen in the mix, and i understand that a lot of people are excited about hydrogen, in fact I suggested it myself when I was a kid, its energy potential is the highest of any of the common elements on the planet, but putting it to practical application has been a tough and arduous journey to say the least, I’m not knocking it at all but we are waaaay to far away from using it in our daily lives yet, a more practical solution right now, that can help EVERYBODY not just those with deep pockets is alternative fuels, Exxon Mobil is helping with one of the most promising solutions I’ve seen, (to bad people weren’t smart enough to help the scientist that thought this up before these guys did now oil companies wont be going out of business) using algae “farms” to suck out the carbon dioxide, and turn it back into fuel again, it would be akin to using solar energy but at a higher efficiency rating than solar panels could ever get plus it uses the carbon dioxide in our atmosphere so we are not re introducing anything in our environment just recycling
oh and jjpro….. YOU need to get your facts straight before you blog dude, or you just look like a jack @ss opening your comment with what you said - 8. wjv Says:
July 23rd, 2009 at 2:12 pm@Art: I’m not sure who you’re responding to, it seems at first like you’re talking to jjpro, but then careen into a tirade against my fuzzy statistics. And you seem to misrepresent what Robot said, and what I said to robot…
I openly admit my figures are fuzzy and I tried to make that clear before I laid them out. It was meant as a back of the envelope type of calculation.
My point was this: even with rough efficiency figures, cumulative energy loss compared between electric cars and hydrogen fuel cell cars leaves the electric car way ahead.
Going back to sum up the figures I had before yields overall 27% energy loss with the electric car, while the hydrogen car has a cumulative 60% energy loss from electricity to fuel.(And that’s ignoring any hydrogen diffusing out of the storage tank).
Again allow me to emphasize that this is a casual calculation from rough figures, but even still the disparity between the two figures gives you reason to pause.My main reason for bringing this up was jjpro’s unsubstantiated claim quoted below:
“Hydrogen systems are just as efficient as pure-electrical-battery systems.” -jjproI asked him for a reference to prove this statement or how he logically arrived at that conclusion, and tried to justify why I was skeptical about it in the first place with a quick calculation. I was just trying to make a suitable post for a forum, I wasn’t trying to get an A on a research paper, here, Art.
- 9. nerfer Says:
July 23rd, 2009 at 4:55 pmDon’t forget that fuel cell stacks cost well over $100K last I heard (they don’t give out the figures very often). A battery-electric system is a tenth of that. We still have work to do to offer everything people want with a BEV, but they’re way ahead in affordability.
Still, a BEV with 150 mile range is more than adequate for most everything but long vacations (rent a hybrid and still be money ahead). We will need options, and perhaps some minor funding for hydrogen will work, but don’t slow down technology we need now and can put into the market within 5 years (hopefully including cellulosic ethanol and natural gas vehicles).
But my next purchase will be a velomobile, for the ultimate in sustainable transportation.
Source: http://blogs.discovermagazine.com/80beats/2009/07/22/hydrogen-car-back-from-the-impound-congress-restores-funding/
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