The article isn't forthcoming about details, but radioactive material falling to earth is only a concern if this uses nuclear power to reach orbit. If they're just talking about a small nuclear reactor as a power source for electronics and an ion engine (or something like that) then the fuel does not become significantly radioactive until it's safely out of earth's atmosphere. Until the reactor is turned on, you can handle the fuel with bare hands.
Slashdot videos: Now with more Slashdot!
We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).
Modern x86 processors translate instructions into a sequence of RISCy operations (which takes quite a bit of silicon), and then operate like any other high-speed processor internally.
Small correction: the AP1000 reactor's lifetime is at least 60 years, not 25.
Remember when Google announced that they were going to offer a webmail service, with a 1 GB storage quota? Everybody thought it was a hilarious April Fools Day joke, and there was no way Google would do something so ridiculous and implausible. Turns out the joke is that they were serious.
Gravity guns are science fiction, but laser brooms could bring down space junk. You fire a laser into space from the earth, and any space junk in its path gets partially ablated, which thrusts it into a more eccentric orbit, which increases atmospheric drag and makes its orbit decay faster.
And this stuff decays orders or magnitude faster. I only mentioned the exponential part because a lot of people don't seem to know it isn't linear.
They have lower per-kWh operating and maintenance costs than coal. A lot of that is the cost of fuel -- coal plants take absolutely vast amounts of coal every single day.
Nuclear power is a great cash cow once you've paid off the amortized cost of building the plant. The cost of operations and maintenance, including the complete fuel cycle and the regulatory paranoia, is so small that electricity from the US fleet of nuclear plants is now cheaper than electricity from coal on a per-kWh basis. The problem is building the plants: you need to raise billions of dollars for licensing, politicking, and the construction of one of the modern gigawatt behemoths. The financial risk is so large that few investors are willing to finance construction of a plant that would be very lucrative in the long run. After all, nuclear plants last at least 60 years, and you only have to build them once.
As for government subsidies, the nuclear industry is actually getting a negative subsidy if you include all the billions of dollars they have to pay the US government to "put their waste in Yucca Mountain", which of course hasn't happened and probably won't happen ever.
The problems with Chernobyl go way past that. Here are a few:
1. Positive void coefficient of reactivity. Once bubbles started forming in the reactor coolant, it sped up the reaction, causing a positive feedback loop. This is, of course, not the case with light water reactors.
2. The SCRAM rods actually sped up the reaction because of their graphite tips. There's a pretty crazy design defect.
3. It was physically possible for those morons to disable the safety systems.
Compare this with a truly modern design like China's HTR-DB modular pebble bed reactors, and the difference is striking. The HTR-DB has a strong negative temperature coefficient of reactivity, so all the feedback loops are very negative. They can actually shut off the cooling systems and the reactor will simply shut off because it's not able to sustain a reaction without active cooling. Overheating inherently kills the reaction. Nice, isn't it?
Energy companies won't develop them because of the large financial risk and paranoid regulatory environment and lack of a clear payoff. Governments won't step in because any nuclear reactor is seen as evil by the green fanatics and seen as threatening by the coal companies.
Wrong. Nuclear thermal rockets use a reactor to heat propellant. It's also possible to have a nuclear reactor producing electricity which is used in an ion drive, which you have unfairly written off; it gets very high specific impulse in space, albeit with small thrust.
Also, there are countries where people aren't irrationally paranoid about anything with "nuclear" in the name. China, for example, is set to start kicking a lot of ass with their HTR-DB mass-produced high-temperature gas-core pebble bed modular reactors. I think when you say "nowhere on earth" you actually mean "nowhere in the United States or Europe".