Courtesy Mark RyanResearchers in Japan are studying the wing structure of dragonflies to help improve how micro wind turbines perform during high winds. Micro turbines are small, affordable energy converters that can be used in both urban and rural settings where giant turbines would be too expensive, too large, and too impractical. Micro turbines can be set up relatively easily in configurations of a single unit or as a bank of several units, and the energy generated can be stored in batteries.
They work on the same principle as the large turbines, but can generate power in wind speeds as low as 4 or 5 miles per hour. One fallback, though, is their generators can get overloaded when hit with high storm winds, producing more energy than the system can handle. Large turbines solve this problem by tilting their propellers - either by computer or otherwise - and adjusting their rotation speed. But that kind of technology just isn’t affordable with micro turbines.
That’s where studying dragonfly wings comes in. Aerospace engineer Akira Obata of Nippon Bunri University in Oita, Japan wondered how dragonflies were able to remain stable in flight at low speeds. He placed a plastic model of a dragonfly wing into a large tank of water laced with aluminum powder and videotaped the flow patterns. He noticed that as the water flow slowed down vortices arose on the wing’s surface that allowed the water to pass over the wing at the same speed, thus keeping it stable. But when water flow sped up the wings aerodynamics performance decreased.
So, Obata developed an inexpensive paper micro turbine with similar “dragonfly wing” bumps on its surface and it did just as he hoped. When air speeds flowing over the turbine wing increased between 15 and 90 mph, rather than speeding up its rotation and overwhelming its battery, the micro turbine curved into a conical shape that stunted rotation and kept power generation low.
You’d probably say, “Huh?? Hold on, what is geothermal energy anyway, and how does it work?”
Geothermal is heat from deep inside the earth. Because heat is a form of energy, it can be captured and used to heat buildings or make electricity. There are three basic ways geothermal power plants work:
(Click here for great diagrams of each of these geothermal energy production methods.)
“And what about carbon sequestration too? What’s that and how does it work?”
Courtesy Department of Energy
Carbon sequestration includes carbon (usually in the form of carbon dioxide, CO2) capture, separation, transportation, and storage or reuse. Plants, which “breathe” CO2, naturally sequester carbon, but people have found ways to do it artificially too. When fossil fuels are burned to power your car or heat your home, they emit CO2, a greenhouse gas partially responsible for global climate change. It is possible to capture those emissions, separate the bad CO2, and transport it somewhere for storage or beneficial reuse. CO2 can be stored in under the Earth’s surface or, according to Martin Saar’s research, used in geothermal energy production.
Alright. We’re back to Professor Saar’s research. Ready to know just how he plans to sequester carbon in geothermal energy production?
It’s a simple idea, really, now that you know about geothermal energy and carbon sequestration. Prof. Saar says geothermal energy can be made even greener by replacing water with CO2 as the medium carrying heat from deep within the earth to the surface for electricity generation. In this way, waste CO2 can be sequestered and put to beneficial use! As a bonus, CO2 is even more efficient than water at transferring heat.
But don’t take my word for it. Come hear Professor Martin Saar’s lecture, CO2 – Use It Or Lose It!, yourself during the Institute on the Environment’s Frontiers on the Environment lecture series, Wednesday, October 27, 2010 from noon-1pm.
Frontiers in the Environment is free and open to the public with no registration required! The lectures are held in the Institute on the Environment’s Seminar Room (Rm. 380) of the Vocational-Technical Education Building on the St. Paul campus (map).
Courtesy Mark RyanA new study appearing in the Journal of Palliative Medicine reports how several terminally ill patients all showed identical surges in their brain activity just before they died. At first the doctors at George Washington University Medical Faculty Associates who did the study thought the surge was being caused by interference from life-support machines or other electronic gear in the room.
“But then we started removing things, turning off cell phones and machines, and we saw it was still happening,” said lead author Lakhmir Chawla.
Speculation of what causes the neurological hyperactivity at the moment of death is that neurons in the brain, suddenly deprived of blood pressure and oxygen, shut down in rapid succession resulting in a final burst of neural activity - an electrical death rattle if you will. But the idea doesn’t seem to be a very new one. Kevin Nelson, a researcher studying near-death experiences at the University of Kentucky claims it’s well known that the brain experiences a sudden discharge of electrical energy when blood flow to it is cut off.
So, I’m not sure I see what the big surprise is here. If this is so well-known then why wouldn’t the doctors at George Washington University Medical Associates already know this?
But there’s another part of this that’s interesting. The surge may also be responsible for the "white light" reported by some patients who have had near-death episodes. The lore surrounding this phenomenon is about patients seeing an intense bright light when they're dying. But, according to Chawla, the majority of people involved in such incidents report having no such “white light” occurrence, but merely a vivid memory that may have been burned into their brain by the “final” electrical discharge.
And what about the so-called "out of body experience" patients sometimes report after slipping from the grasp of the Grim Reaper? Well, that, too, could come from the brain's electrical shutdown. A study that appeared in the journal Nature in 2006 reported patients sensing "shadow figures" laying nearby, or hovering above while certain areas of their brains were being stimulated with electrical currents. The charges interfered with the sensory information being received by the brain, and the hallucinations were just the brain's way of making senses of everythingl. The New York Times ran a story about it you can read here.
Bottom line, it looks like all those reported supernatural near-death experiences are just all in your head.
Courtesy Tallia Miller
Cooking food on an open fire may sound romantic but in reality breathing smoke and scrounging for fire wood make it not so pleasant. It is estimated that the smoke from cooking fires leads to nearly 2 million premature deaths each year.
A Global Alliance for Clean Cookstoves has formed to
"save lives, improve livelihoods, empower women, and combat climate change by creating a thriving global market for clean and efficient household cooking solutions."
A better burning stove should not be rocket science but several factors should help the Alliance meet their goal of 100 million households converting to clean cookstoves and fuels by 2020.
Starting with several existing cutting-edge technologies, NASA might be able to develop a way to catapult satellites and spacecraft into orbit.
An early proposal has emerged that calls for a wedge-shaped aircraft with scramjets to be launched horizontally on an electrified track or gas-powered sled. The aircraft would fly up to Mach 10, using the scramjets and wings to lift it to the upper reaches of the atmosphere where a small payload canister or capsule similar to a rocket's second stage would fire off the back of the aircraft and into orbit. The aircraft would come back and land on a runway by the launch site. NASA.gov
Making the impossible, possible - one prize at a time. This is the idea behind the X-prize movement. Flying into space, cleaning up oil spills, landing on the moon, or producing safe, practical cars that get 100 mpg are becoming reality as teams compete to win X-prizes.
To drive innovation, offer the right prize and human nature will do the rest.
Did Archimedes use a heat ray to set enemy ships on fire over 2000 years ago? A text written about the Siege of Syracuse (212BC) some 400 years later merely said he lit the ships on fire. He could have used flaming arrows or perhaps hurled larger balls of flame via catapult.
Anthemius of Tralles mentions burning-glasses as Archimedes' weapon.
This purported weapon has been the subject of ongoing debate about its credibility since the Renaissance
In 1973, an experiment using 70 mirrors, each with a copper coating and a size of around five by three feet, caused a mock-up ship 160 feet away to burst into flames within seconds.
A group of MIT students used a parabolic array of 127 "polished metal mirrors" 1 sq ft in size for a 2005 MythBusters episode and were barely able to set part of the "ship" aflame.
I recently came across this video of a recreation of the Archimedes heat ray experiment.
Courtesy wvs (Sam Javanrouh)In a paper delivered at the 240th National Meeting of the American Chemical Society in Boston, a researcher envisioned a time in the not-too-distant future when houses and buildings outfitted with the proper equipment would be able gather electric energy stored in humidity in the atmosphere that could be used to fill a community’s electrical needs.
The concept isn’t new; electrical wunderkind Nikola Tesla had a similar idea more than a century ago.
Science has long sought the answer to how electricity builds up and discharges in the atmosphere, and whether the moisture in the atmosphere could even hold an electrical charge. But Fernando Galembeck, a professor at Brazil’s University of Campinas, claims he and his research team have successfully shown that it can, and by using special metal conduits to collect that electricity, it could allow homeowners and building managers to gather and store the electricity as an alternative energy source.
”Just as solar energy could free some households from paying electric bills, this promising new energy source could have a similar effect,” Galembeck said. He terms the new method “hygroelectricity” which means “humidity electricity”. Galembeck's research could also add to our understanding of how thunderstorms form.
In their laboratory experiments, Galembeck’s research team created a simulated atmosphere densely saturated with water (humidity), which they seeded with silica and aluminum phosphate, two chemical compounds commonly found in air. As water droplets formed around the tiny, airborne chemical substances, the researchers noticed the silica took on a negative charge while the aluminum phosphate droplets held a positive charge. The charged water vapor readily condenses upon contact with surfaces such as a cold can of soda or beer, and on the windows of air-conditioned buildings or vehicles. In the process, energy is transferred onto the contact surface.
“This was clear evidence that water in the atmosphere can accumulate electrical charges and transfer them to other materials it comes in contact with,” Galembeck said.
Just as solar panels convert energy from sunlight into a usable power source, the researchers think water vapor in the atmosphere could someday be harvested for its hygroelectric energy. The rooftops of buildings in regions of high humidity and thunderstorm activity could someday be fitted with special hygroelectric panels that would absorb the charges built up in the humid atmosphere and funnel the energy to where it can be utilized, and at the same time reduce the risk of lightning forming and discharging. The technology would be best suited to regions of high humidity, such as the tropics or the eastern and southeastern U.S.
Thunderstorm over Lake Harriet in Minneapolis; Could this be a new source of energy for the Upper Midwest?
I have waited almost two years for this race. What kind of automobiles can qualify to win the $10 million Automotive X Prize?
The Zap Alias seems to be the favorite.
Validation is the final technical event in the Progressive Insurance Automotive X PRIZE. Finalists in both the Mainstream and Alternative classes will undergo dynamometer testing under controlled laboratory conditions at Argonne National Lab facilities. The car in each class that exceeds 100 MPGe, meets the emissions and performance requirements, and, in the case of a tie, completes the Combined Performance and Efficiency challenge with the fastest time, will win. The $10 million prize purse will be presented at an Award Ceremony on September 16, in Washington, D.C.
Courtesy Mark RyanOld Sol could be stirring up the atmosphere this evening with a display of northern lights (aurora borealis). Scientists have recorded a significant burst of plasma shooting from the Sun’s surface that could mean we earthlings are in for a light show tonight or early Wednesday morning. The solar wind particles are headed right toward us, and when they reach the Earth’s magnetic field they’ll interact with atoms of nitrogen and oxygen in the atmosphere and - hopefully - produce glowing sheets and fingers of green, red, blue, or even yellow in a wonderful display in the northern skies. The southern hemisphere experiences the same phenomenon but down there it’s known as the aurora australis (southern lights).
Lately, here in the Twin Cities, the air has been supersaturated with humidity so I don’t know how crisp a view we’ll get but it could be worth stepping outside tonight to see what’s up.