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Comment Re:About time. (Score 1) 309 309

Nuclear reactors don't need water. You can build liquid metal cooled reactors. Metallic sodium is one such metal used.

Although some reactors have been built with liquid metal cooling, nearly all have been experimental reactors only. However, even in liquid metal cooled reactors, generally the turbine that actually generates the electricity is driven using a steam cycle (which uses water). So technically a nuclear reactor doesn't need water, but generally you want electricity out such a reactor (unless you are using it simply to generate transuranic elements)...

you can use the mercury vapor cycle or even a boiling sodium vapor cycle with a turbine. Both have a thermal efficiency advantage over steam cycle. Further more you can use either of those cycles in combination with a steam cycle thus creating a binary cycle that has a thermal efficiency above 50%.

Comment The nuclear power industry doesn't target anything (Score 0) 3 3

The nuclear power industry doesn't target anything. Nuclear power is a technology. It has advantages. It has disadvantages. The nuclear industry competes with all other types. It competes with wind and solar in that it doesn't emit green house gases. One of its main advantages is it doesn't fluctuate on external conditions. This is an area where wind and solar can't compete. Because of this wind and solar proponents claim they are being targeted.

Submission + - Progressing Being Made in Renewable Energy Storage Technologies-> 2 2

dave562 writes: As astute Slashdot commentators frequently mention when renewable energy is discussed, the biggest challenge faced by renewable energy is its inability to provide stable baseline power. Progress is being made to address those concerns, and companies who can deliver successful are trying to tap into a market that has been valued at $10.5 billion dollars.

From the article,

"The problem for a lot of renewable power sources — wind and solar farms, run-of-river hydro — is that they often pump out the most power when utilities don’t need it, but dim down when they really want it.

For electric utilities, balancing those peaks and valleys from intermittent energy sources is a major challenge to integrating them into the grid, which is why some B.C.-based firms are hoping to cash in on the development of energy-storage technologies.

ZincNyx’s technology, the so-called flow battery, is a regenerative fuel-cell system that takes in electricity when the power isn’t needed and uses it to create fuel out of zinc-oxide that is stored in a tank, and which is then run through a fuel cell that converts it back into electricity when it is needed."

Is this the answer to the challenge faced by renewable power? What other hurdles still remain?

Link to Original Source

Submission + - Patent awarded for stealing energy from passing cars to power electrical devices->

Obscene_CNN writes: New Energy Innovations is not the first to try to tackle the concept. Company founder Ralph Black describes it as a series of vertical pumps, similar in design to a stand-up bicycle pump. They’re buried in the road surface inline and when a car drive over it it compresses air that can be used to turn a generator.

Shamefully they have the University of Illinois at Chicago Mechanical and Industrial Engineering Department collaborating with them on this. Apparently they know nothing about thermodynamics as it would take far less energy to drive a generator directly with an engine and create less pollution rather than syphon energy off of an already inefficient car rolling by.

The company is planning a crowdfunding campaign so keep an eye out for it so you can flame and shame them.

Link to Original Source

Submission + - Navy: More railguns and lasers, less gunpowder->

coondoggie writes: “Number one, you’ve got to get us off gunpowder,” said Greenert, noting that Office of Naval Research-supported weapon programs like Laser Weapon System (LaWS) and the electromagnetic railgun are vital to the future force. “Probably the biggest vulnerability of a ship is its magazine—because that’s where all the explosives are.”
Link to Original Source

Submission + - Microsoft is reading the email of child pornographers

GordonFive writes: A man and wife in Palmer Alaska were recently arrested for child pornography and child abuse
This story in it self is not what caught my eye, but apparently according to the Alaska State Trooper Press release Case Numbers: AK14064393 they were turned in by Microsoft Corporation who had discovered the man attempting to email child porn to another party.
Microsoft is evidently reading peoples email.

Submission + - Triggering Force of Alkali Metal Explosions Revealed->

Kunedog writes: Years ago, Dr. Philip E. Mason (aka Thunderf00t on Youtube) found it puzzling that the supposedly "well-understood" explosive reaction of a lump of sodium (an alkali metal) dropped in water could happen at all, given such a limited contact area on which the reaction could take place. And indeed, sometimes an explosion did fail to reliably occur, the lump of metal instead fizzing around the water's surface on a pocket of hydrogen produced by the (slower than explosive) reaction, thus inhibiting any faster reaction of the alkali metal with the water. Mason's best hypothesis was that the (sometimes) explosive reactions must be triggered by a Coulomb explosion, which could result when sodium cations (positive ions) are produced from the reaction and expel each other further into the water.

This theory is now supported by photographic and mathematical evidence, published in the journal Nature Chemistry. In a laboratory at Braunschweig University of Technology in Germany, Mason and other chemists used a high-speed camera to capture the critical moment that makes an explosion inevitable: a liquid drop of sodium-potassium alloy shooting spikes into the water, dramatically increasing the reactive interface. They also developed a computer simulation to model this event, showing it is best explained by a Coulomb explosion.

The Youtube video chronicles the evolution the experimental apparatuses underwent over time, pursuant to keeping the explosions safe, contained, reliable, and visible.

Link to Original Source

Submission + - Cosmonauts Carried Sawed-Off Shotgun on Space Missions writes: James Simpson has an interesting story about the TP-82 survival pistol that Russian cosmonauts carried into space with them on missions between 1982 and 2006. But calling it a pistol is slightly misleading—the TP-82 was essentially a sawed-off, double-barreled shotgun with a short-barreled rifle added onto it. Having a gun inside a thin-walled spacecraft filled with oxygen sounds crazy, but the Soviets had their reasons. Much of Russia is desolate wilderness. A single mishap during descent could strand cosmonauts in the middle of nowhere. In March 1965, cosmonaut Alexey Leonov landed a mechanically-faulty Voskhod space capsule in the snowy forests of the western Urals 600 miles from his planned landing site. For protection, Leonov had a nine-millimeter pistol. He feared the bears and wolves that prowled the forest—though he never encountered any. But the fear stayed with him. Later in his career, Leonov made sure the Soviet military provided all its cosmonauts with a survival weapon. For the Soviets, the weapon was a case of “better safe than sorry,” and from 1986, it was a permanent fixture in the portable survival kits of every Soyuz mission. "Astronauts of all nationalities—including Americans—have trained with the TP-82," writes Simpson. "And still today, before they ride the Soyuz to space, they must complete a Russian survival training course in the Black Sea and the Siberian forest."
