Stories tagged alternative energy
Snake power: It looks like an ordinary tube, but this device is a small version of the Anaconda, a snake-like tube that turns ocean wave power into electricity.
Courtesy Atkins GlobalIndiana Jones may hate snakes, but those looking for clean, renewable energy sources are loving the chances that a “snake” may be able to generate electricity from ocean waves.
It’s not a real snake, but an enormous rubber snake called the Anaconda. Stretching more than 600 feet long, the Anaconda produces energy as it is squeezed by the passing waves of ocean water that it is submerged in. The process is very similar to what happens with a windsock fluttering in the wind.
The Anaconda is filled with seawater and is sealed at both ends. The trailing end of the snake has turbines. As the ocean waves ripple by the Anaconda, the water inside is squeezed and pushed in bulges that move toward the turbines. When the bulges get there, their energy turns the turbines.
The idea is being developed by the British firm Atkins Global. This is all still in the testing stages, but if the research pans out, the Anacondas would be submerged in ocean waters at depths of 120 to 300 feet.
So far, however, researchers are testing their theory on smaller snakes in a wave tank. Seawater testing could begin next year and if everything is successful, the technology could go online commercially in five years. Estimates figure one full-sized Anaconda could generate 1 megawatt of electricity, about the same amount of power for 2,000 homes.
Tags : Another dismal post about the dismal science.
Today, we look at The Copenhagen Consensus. A group of economists are presented with a thought experiment: let’s say you had $75 billion to spend on solving one of the world’s problems – how would you allocate your funds?
Economists, being the dismal people that they are, take no account of what is “moral” or “right” or what “ought” to be done. They just try to figure out where you get the biggest bang for your buck. Their answer? Micronutirents for kids. Providing vitamin A and zinc to 80 percent of the 140 million children who lack them would provide almost $17 in health benefits for every dollar invested.
Other items in the top ten:
- Micronutirents for kids
- Expanding free trade
- Fortifying foods with iron and salt
- Expanding immunization coverage of children
- Biofortification
- Deworming
- Lowering the price of schooling
- Increasing girls' schooling
- Community-based nutrition promotion
- Support for women's reproductive roles
The majority of the most-efficient solutions deal with health, thus proving the old saying, an ounce of prevention is worth a pound of cure.
The least-efficient proposal was a plan to mitigate global warming. Nobel Prize-winning economist Thomas Schelling noted that that spending $75 billion on cutting greenhouses gases would achieve almost nothing. In fact, the climate change analysis presented to the panel found that spending $800 billion until 2100 would yield just $685 billion in climate change benefits.
Economist Richard Nordhaus, in his book A Question of Balance: Weighing the Options on Global Warming Policies, draws a similar conclusion. Projects to massively reduce greenhouse gases end up costing more than they deliver—in some cases, many trillions of dollars more. OTOH, investing in alternative energy (wind, solar, etc.) and bio-engineering can produce great results for the amount spent on them.
The economists at Copenhagen felt funding research and development of low-carbon energy technologies was worthwhile, and ranked it 14th out of the 30 proposals they considered.
Other items at the bottom of the priorities list are proposals to reduce air pollution by cutting emissions from diesel vehicles; a tobacco tax; improved stoves to reduce indoor air pollution; and extending microfinance. These are not necessarily bad ideas. It’s just that other proposals provide more bang for the 75 billion bucks.
Here comes the Sun: Scientists announce new breakthroughs in solar energy technology. Photo by S4N7Y from Flickr.com
A company in Massachusetts has developed a process for producing solar power cells using inkjet printers. This could drastically reduce the cost of producing the cells, and increase the number of ways they are used.
Meanwhile in Atlanta, Lonnie Johnson – the man who invented the Super Soaker squirt gun – is working on a solar-powered electrical generator that would be twice as efficient as current models.
Most ethanol is currently made from corn. Scientists in Europe are worried that increasing production for ethanol will increase the demand for the crop, thus leading cut down forests to plant more corn. This would have a greater negative impact on the global climate than any positive impact from using ethanol instead of gasoline.
Meanwhile, researchers at the University of Minnesota and some place called "Princeton" have learned that converting forests and prairies into farmlands to grow corn actually releases carbon into the atmosphere, far more than is saved by replacing gas with ethanol.
OTOH, this author claims there is no evidence that forests and prairies are being converted to farm land. Rather, the demand for corn is being met by more efficient farming. He also argues that ethanol is cost-efficient and does not lead to higher food prices.
Biomechanical Energy Harvester: In the very near future, taking a brisk walk may not only recharge your batteries but will also recharge your cell phone and iPod batteries.
Courtesy Simon Fraser UniversityOur man Thor recently posted a story about an energy-producing fabric that in the near future will enable you power an iPod or other electronic device just by wearing it, like as a shirt or maybe underwear. But it sounds like you’d have to do a heck of a lot of moving around just to get it to power a single phone call. And to tell you the truth, it looks pretty itchy to me, and would probably shrink in the wash. So personally, I’d much prefer having something strapped to my knees that harvests the energy created by my walking or running, and use that to charge my favorite electronic gizmo.
Well, now I guess some engineers in Canada and the U.S. have developed just such a device: a modified knee brace that harvests energy expended while you walk. And instead of a measly 80 milliwatts of electricity (like a square meter of the fabric would produce), this device can produce something like 5 watts! The team, which included researchers from the University of Pittsburg and the University of Michigan, published their findings in the journal Science.
The device is called the Biomechanical Energy Harvester, and what's cool is the way it captures the energy. While a person’s walking, it turns itself on and off at critical moments during the stride in order to gather the energy while the user’s leg is involved in what’s termed negative work. That’s when the leg has completed its swing forward and its foot is on the ground decelerating while the other leg is beginning the positive work of swinging forward.
"If you want power, go where the muscles are," said Max Donelan, professor of kinesiology at Simon Fraser University, in British Columbia. "We thought, maybe there's a smart, selective way to do energy harvesting when muscles are normally decelerating in the body."
The brace then switches off just as the leg begins its positive work again. If it didn’t do this the device it would hinder the forward motion of the leg.
“That engagement and disengagement happens once the stride is at the region where your muscles need the help at the end of the swing phase. It actually assists them in decelerating that extra resistance,” Donelan said.
At the same time, the gadget is also producing electricity. It’s similar to how a hybrid automobile charges its batteries while braking. You can see the brace in action here.
Right now the prototype is cumbersome and weighs in at about 3.5 pounds but a lightweight version could be available within the next 18 months. Donelan, who led the research, thinks the brace could have applications in the medical field, and also be used by hikers or soldiers to power GPS devices or satellite telephones where no other source of electricity is available.
With a brace on each leg, the user could generate up to 13 watts of electricity depending how fast they moved. To put it in more practicable terms, a one-minute stroll wearing the bionic knee brace could harvest enough energy to power a ten-minute cell phone call.
New energy source?: Wildcatters may soon be turning their attention to kneecaps.
Courtesy euthmanGoodness gracious, just think of all the megawatts of electricity that could be harvested at the Boston or New York Marathons each year. It could mean the antiquated term “horse power” may soon be replaced by “knee power”.
LINKS
SFU press release
Research lead Max Donelan explains device (Large file - may take a little while to download)
It’s a little early, but Popular Science has issued their list of the top innovations of 2007. Their grand prize winner are nanosolar powersheets, thin flexible films that use nanotechnology to harness solar energy -- and allowing me to tag this post as both "nanotechnology" and "energy." The health innovations section allows me to use the "health" tag, and a new toilet that uses 40% less fresh water allows me to tag this as "water." It's a win-win-win!
Researchers at Penn State University have developed a fuel cell in which common bacteria produce copious amounts of hydrogen. Some experts believe hydrogen will replace oil as the fuel of the future, if we can find a way to produce it cheaply. The new apparatus uses waste water, plant material and bugs to produce hydrogen.
Recent comments
Disney's new princess
The worst job in America?
Sociology surprises no one, depresses scientists: guess who’s a virgin?
Sociology surprises no one, depresses scientists: guess who’s a virgin?
Subscribe
I want to learn about
Science Buzz and all related activitiesScience Museum of Minnesota, 2004-2008,
except where otherwise noted.
Copyright Information
Add a new comment