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Penny-Sized Nuclear Batteries Developed
pickens writes "Nuclear batteries that produce energy from the decay of radioisotopes are an attractive proposition for many applications because the isotopes that power them can provide a useful amount of current for hundreds of years at power densities a million times as high as standard batteries. Nuclear batteries have been used for military and aerospace applications for years, their large size has limited their general usage. But now a research team at the University of Missouri has developed a nuclear battery the size of a penny that could be used to power micro- and nano-electromechanical systems. The researchers' innovation is not only in the battery's size, but also that the batteries use a liquid semiconductor rather than a solid semiconductor. 'The critical part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure of the solid semiconductor,' says Jae Wan Kwon. 'By using a liquid semiconductor, we believe we can minimize that problem.' The batteries are safe under normal operating conditions. 'People hear the word "nuclear" and think of something very dangerous,' says Kwon. 'However, nuclear power sources have already been safely powering a variety of devices, such as pacemakers, space satellites, and underwater systems.'"
Refineries ... Actually that was exactly Ahmadinejad's main election promise way back ... to rebuild the refineries. He tried. He tried really hard, really really really hard, and failed. (ever notice how strange it is that the dictator's "main puppet" of a theological state holds a phd in civil engineering and has taught at the best university of the country ? His sons, of this theocratic dictator, are on the way to degrees in civil engineering, again one would assume they'd see more future in religious studies, but clearly daddy theocratic dictator doesn't see much future in all that allah babbling ...). That said, if you read stories of his actions as mayor of Teheran, one thing cannot be denied : this is a serious thick-headed and stupid idiot. His actions during the "revolution" justify adding "extremely dangerous" to the "lunatic" description of his character (said "revolution" started out as a socialist/communist revolution, ended with the likes of ahmadinejad killing tens of thousands of people until the current Iranian state came into existence). Up to this day there is a big non-functional refinery standing on the outskirts of Teheran, built by Ahmadinejad. It doesn't work but it has what roughly translates to "yes we can" on the front gate. It is considered something between a failure and a sick joke by Iranians.
But the point I wanted to make, about Iran's intentions. Or more specifically, it's islamic theocratic dictator-nutcase's intentions :
There are different types of nuclear plants. You have lightwater plants and heavy water plants. (light water and heavy water denoting the isotopes of hydrogen in said water).
Light water plants are cheaper, easier to build and more energy efficient. They can be made in all sorts of power output levels (meaning they're capable of "low" output too). They can be built the size of a car up to the size of a small town. Their waste is far less toxic than the alternatives. Furthermore, they have far easier fuel requirements. They cannot, however, be used to build a bomb. They do not produce plutonium. They do not produce pollonium. They do not ... Some fuel (found in Iran) does not even need to be enriched to be used in these reactors. All modern western reactors are of this type because of the obvious advantages (only exceptions being 1 medical research reactor, which are slowly becoming obsolete)
Heavy water reactors, the first type designed, are very, very big reactors (the power device itself is very small, but you need big structures surrounding them to absorb the massive power they produce, so you cannot have small plants). They produce power in the hundreds of megawatts at least. They produce heavy elements and highly radioactive isotopes as waste product. They are very picky in the fuel they use, and will only tolerate relatively highly enriched uranium.
Guess which type of reactor Iran is building ? (hint : they wouldn't need a heavy water plant for one of these types)
Also : to enrich fuel for even a heavy water reactor they'd need a relatively small enrichment facility, having a cascade of at most a few dozen centrifuges. They did not do this, instead they've built a cascade of over 6000 centrifuges (meaning they're connected centrifuge 1 -> 2 -> 3 -> 4 -> ...). You do not need a cascade like this for power requirements, in fact it's a huge waste of power (these things need more energy per piece than Al Gore's house and boats combined).
Incidentally that cascade is precisely the critical part necessary for bomb construction (and totally useless and hopelessly inefficient for any other purpose).
Of course these facts are total coincidence and if you feel more secure ignoring this, don't let me stand in your way ...