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853 Articles

Stellarator Is Germany’s Devilishly Complex Nuclear Fusion

November 2, 2015 by 82 Comments

You may not have heard of a Stellarator before, but if all goes well later this month in a small university town in the far northeast of Germany, you will. That’s because the Wendelstein 7-X is finally going to be fired up. If it’s able to hold the heat of a fusion-capable plasma, it could be a huge breakthrough.

So what’s a stellarator? It’s a specific type of nuclear fusion containment geometry that, while devilishly complex to build and maintain, stands a chance at being the first fusion generator to achieve break-even, where the energy extracted from the fusion reaction is greater or equal to the energy used in creating the necessary hot plasma.

There’s an awesome video on the W7-X, and some of the theory behind the reactor just below the break.

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Bioluminescent Challenge Has Students Feeding Their Lamps

October 20, 2015 by 11 Comments

[Tom Lombardo] is an engineer and an educator. When a company sent him a Dino Pet–a bioluminescent sculpture–he found it wasn’t really usable as a practical light source. He did, however, realize it would be an interesting STEAM (science, technology, engineering, art, and math) project for students to produce bioluminescent sculptures.

The lamps (or sculptures, if you prefer) contain dinoflagellates which is a type of plankton that glows when agitated. Of course, they don’t put out a strong light and–the main problem–you have to agitate the little suckers to get them to emit light. [Tom] found that there was a mild afterglow when you stop shaking, but not much. You can get an idea of how much light they make in the video below. The idea for a school project would be to make practical ambient lighting that didn’t require much input power to agitate the plankton.

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Guinea pig power

Guinea Pig Methane Power!

October 18, 2015 by 44 Comments

Half-way around the world, a couple in Peru is harnessing the power of guinea pig poop, to generate methane for their farm. We couldn’t make that up if we tried.

The couple are a pair of retired plant physiology professors who have taken to running a sustainable agriculture program in their very own villa called Casa Blanca. It’s a beautiful set of gardens complete with a lab for research. But the most curious thing is the thousand guinea pigs they raise. They have a special shed for them with small compartments separated by brickwork. The guinea pigs eat specialized plant waste, and in turn, produce an astonishing 3 tonnes of fecal matter per month.

They use around 200kg of the excrement to power their very own bio-digester which in turn produces 3 cubic meters of methane per day which they use for powering their villa. The rest of it is used for fertilizer that they sell to local farms.

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bio gas generation

Washington DC Electrified With Raw Sewage

October 16, 2015 by 25 Comments

Completely unrelated to the current political climate in the United States, did you know Washington D.C. is partially powered by a sewage plant? No, seriously.

That’s right, just this week the D.C. Water utility company has announced a bioenergy facility that makes use of resident’s waste water into producing methane gas which can than be burned to generate electricity — To the tune of 10 megawatts! The facility is saving the company an estimated $10 million a year in energy bills.

Simply put, the liquid is removed from the sewage water and the solids are refined into a type of fuel. Those solids are heated, mixed, and sterilized into a form that can be easily digested by a certain type of microbe, which then in turn produce methane for burning. For a more detailed explanation, check out the info-graphic from the Washington Post explaining the entire process.

And on a smaller scale, you could do something like this in your very own backyard.

Mr. Trash Wheel Cleans Baltimore’s Harbor

October 14, 2015 by 40 Comments

Quite frankly we’re rather surprised we haven’t heard of Mr. Trash Wheel before. It’s a community project by the Baltimore Waterfront’s Healthy Harbor program where they are trying to make the harbor both swimmable and fishable by 2020. One of the coolest projects that resonates with us is Mr. Trash Wheel — a waterwheel-powered-trash-collecting-conveyor-belt. Say that 10 times fast!

It was built in early 2014, and according to the latest data it has removed a whopping 160 tons of garbage from the waterway already. Floating buoy-nets direct the garbage floating on top of the water into a narrow passage where the conveyor belt powered by a waterwheel slowly picks up the trash, and then deposits it into a large dumpster on a barge.

In fact, it’s even saved a python from the water too!

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Optical Rectenna Converts Light To DC

October 9, 2015 by 39 Comments

Using multiwall carbon nanotubes, researchers at Georgia Institute of Technology have created what they say are the first optical rectennas–antennas with rectifiers that produce DC current. The work could lead to new technology for advanced photodetectors, new ways to convert waste heat to electricity and, possibly, more efficient ways to capture solar energy.

A paper in Nature Nanotechnology describes how light striking the nanotube antennas create a charge that moves through attached rectifiers. Challenges included making the antennas small enough for optical wavelengths, and creating  diodes small enough and fast enough to work at the extremely short wavelengths. The rectifiers switch on and off at petahertz speeds (something the Institute says is a record).  Continue reading “Optical Rectenna Converts Light To DC” →

Sensor Net Makes Life Easier For Rice Farmers

October 5, 2015 by 48 Comments

Rice is cultivated all over the world in fields known as rice paddies and it is one of the most maintenance intensive crops to grow. The rice paddy itself requires a large part of that maintenance. It is flooded with water that must be kept at a constant level, just below the height that would keep rice seedlings from growing but high enough to drown any weeds that would compete with the rice stalks for nutrients. This technique is called continuous flooding and a big part of the job of a rice farmer is to inspect the rice paddy every day to make sure the water levels are normal and there are no cracks or holes that could lead to water leakage.

This process is labor intensive, and the technology in use hasn’t changed much over the centuries. Most of the rice farmers in my area are elders with the approximate age of 65-70 years. For these hard working people a little bit of technology can make a big difference in their lives. This is the idea behind TechRice.

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