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US Plans "Disposable" Nuclear Batteries
holy_calamity writes "A US government program is in the works to design small nuclear reactors for use by developing countries. The work continues despite fears about security and nuclear proliferation. Plans include having reactors supplied with fuel by the US and other trusted nations, or to build reactors with their whole lifetime of fuel packaged securely inside — like a giant non-user replaceable radioactive battery.' '"
Reactor grade uranium is 3-4% Uranium-235 (the dangerous kind), and weapons grade uranium is 90% U-235. It takes an order of magnitude more equipment to reach even a crude weapon's level at 20% 235. It even says in the article that the uranium enrichment and processing won't be done on-site.
Most modern reactors use a sealed coolant system, where the coolant that circulates through the reactor is in a sealed loop.
A heat exchange device is used to transfer heat from the sealed coolant system to another system using ordinary methods to dissipate.
No salt water every actually goes into the reactor, or even near it. That would be idiotic.
You are just misinformed. USA foreign aid as a percentage of the GDI is the lowest of just about any developed country:
http://markc1.typepad.com/relentlesslyoptimistic/images/foreign_aid_chart1.GIF
Most of that aid goes to (semi)developed countries like Colombia, Israel and Egypt for political reasons, or to Iraq and Afganistan (which we fucked up in the first place), instead of to the poorest countries in the world:
http://static.flickr.com/51/189662626_257b15004f_o.jpg
Negative moral value of force outweighs the positive value of good intentions.
Why the AC modded down? He's absolutely right. In a nuclear submarine, the coolant loop within the reactor is completely sealed. It pulls heat from the reactor, goes through a heat exchange where it dumps the heat into a second loop, which then flashes into steam to drive a turbine. The steam is then cooled again (presumably with seawater at that stage), across yet another heat exchange. Sea water doesn't even come close the reactor. The only time it ever does is when you seriously need to stop the reactor and dump all your heat. My understanding that this type of scram will basically fuse your entire reactor into a solid radioactive lump.
Not exactly. Pebble bed reactors aren't prone to large catastrophic explosions, like Chernobyl, they still can have serious accidents and radiation leaks. Google Hamm-Uentrop West Germany THTR-300 PBMR. That 300-megawatt reactor was shut down by the German goverment, after an accident in the reactor, on May 4 1986, that damaged the fuel pebble's cladding and released radiation into the area surrounding the plant. Pebble bed reactors are not as 'safe' as people say, nor would I call the nuclear waste they leave 'clean.'
Is there any reason why people can't buy solar panels and put them on their roofs? Are they too expensive? Ugly? Do they not provide enough power for the average home?
1. Nope
2. Very much so
3. Beauty is in the eye of the beholder
4. Sure, you just need a lot of them, not to mention a storage bank if you want power when the sun's not out.
Limited exceptions aside, the only thing keeping solar from being part of the standard roof installation is that even with 50-75% subsidization on the part of various government agencies the payback is over 20 years in most cases. If you assume a 5-10% cost of capitol, many systems would never break even.
Cut the cost of panels in half and double the cost of electricity and it makes sense in orders of magnitude more places, such as areas where electricity is extremely expensive, such as some European countries and California when the legislature is having a particularly large cow.
Get the cost of an install that'll cover ~50% of a home's needs down to ~$2-4/watt and I'd expect them to be building factories to build the panels left and right. I say 50% because more than that and you'll likely need battery banks($$$) to go off the grid otherwise the power companies will start doing things like charge a monthly connection fee to pay for infrastructure and maintenance, and refuse to buy power because they have no demand when you have power to sell.
A single watt of panel can be expected to produce ~2-3 kwh a year. If you're paying $.30 a kwh, you're looking at a payback period of around 4-5 years. That's reasonable. The problem: I haven't seen a new panel kit for less than $10/watt, and I only pay $.10 per kwh. So I'm not installing them anytime soon.
I don't read AC A human right
http://www.dangerouslaboratories.org/radscout.html
...
He started with smoke detectors (americium), moved up to radium, the uranium.
"When David's Geiger counter began picking up radiation five doors from his mom's house, he decided that he had "too much radioactive stuff in one place" and began to disassemble the reactor. He hid some of the material in his mother's house, left some in the shed, and packed most of the rest into the trunk of his Pontiac."
"At the shed, radiological experts found an aluminum pie pan, a Pyrex cup, a milk crate and other materials strewn about, contaminated at up to 1000 times the normal levels of background radiation. Because some of this could be moved around by wind and rain, conditions at the site, according to an EPA memo, "present an imminent endangerment to public health."
After the moon-suited workers dismantled the shed, they loaded the remains into 39 sealed barrels that were trucked to the Great Salt Lake Desert. There, the remains of David's experiments were entombed with other radioactive debris."