Robots Enter Fukushima Reactor Building

swandives writes "For the first time, a pair of remote controlled robots have entered a reactor building at the stricken Fukushima Daiichi nuclear power plant. Plant operator Tokyo Electric Power hopes the iRobot Packbots will be able to provide data on the current condition inside the buildings, although the company hasn't yet released any information on what they found inside."

Re:Jerry Pournelle's *rational* view of Fukushima

[pushing-robot]

Ah, yes:

Backwards Chile, [google.com]
backwards Indonesia, [google.com]
backwards Alaska. [google.com]

Nope, no civilization there.

All energy is nuclear

[symbolset]

Geothermal is also nuclear power. It relies on the intrinsic fission of elements within the Earth's mantle, and legacy heat from prior fission as well as legacy friction from planetary formation. It's implemented by steam turbines also, or turbines driven by the flash evaporation of some other coolant.

The difference betweent fission, fusion and geothermal is that geothermal requires no fuel creation or elimination. You dig two deep holes fairly close together and force water down one of them. The heat of the Earth heats the water, which comes up the other hole - usually as steam or superheated water that will become steam when the pressure is released, but sometimes just as much hotter water. Naturally after the energy gained is tapped, the hot water is then re-injected. For new water some use sewage effluent and solve two problems at once. There is no ash, no spent fuel to rot in casks 100,000 years under close supervision of a non-proliferation task force. There are no mining deaths because there's no mine. There are no refining risks because there's no refining. There's no proliferation risk because there's no nuclear products onsite. The cost of dealing with the emissions are well understood because there aren't any. Geothermal plants require a much smaller geographic footprint than even nuclear plants, because they can mine energy from several miles in each direction and there is no risk.

With geothermal power in the event of a disaster of the worst possible sort: a Geothermal plant is simultaneously attacked by terrorists, crushed by a 10.3 earthquake and inundated by the subsequent 90m tsunami at the exact moment that a Justin Bieber album goes platinum, the worst that can happen is that some steam will vent and electricity will stop being generated, and Justin Bieber gets a slot on Dancing With the Stars. That's not a lot of downside risk, relative to fission and fusion.

There are established economies on Earth that can't provide 100% of their electrical energy needs from geothermal sources. Some parts of Africa, the US East Coast, Brazil. Japan, though? Yes, they could. Their entire nation is a chain of active volcanos. They are geothermal rich beyond the dreams of avarice.

Re:Oh, a nuclear energy thread.

[larkost]

Actually, thus far every design type of theoretical fusion plant would necessarily create radioactive waste, although not as much of it as fission plants. The reason is the same one that the waste-water in the original article is a problem: nuclear reactions work by massive cascades of nutrons randomly hitting atoms in the core. When those nutrons hit the nucleus of an atom (in a way that causes them to be absorbed in the right way), then you get your nuclear reaction, and that in turn produces more neutrons as ersatz-billiard-balls to continue your reaction, plus energy (in the form of heat) that you harvest off (usually with water) to convert into your power-transmission method of choice (usually electricity).

The problem in all of this is that you can't just limit it to your fuel and your energy harvester (water), you wind up with lots of other elements in the reaction chamber that also get bombarded with neutrons. And some percentage of those elements are going to wind up transmuting into radioactive waste.

In the case of a fusion reactor that is probably going to be whatever serves as the reaction chamber wall. Remember, neutrons are magnetically/electrically neutral particles, so you can't contain them using magnets, so you just have to let your reactor wall take the hits, and slowly degrade into radioactive waste. No one has a solution to this problem, and it is unlikely that one exists.

So, there really is no pedantic to call out here. Nuclear energy produces nuclear waste, the only question is how much (vs. the extracted energy), and how bad the byproducts will be.

Re:kidding

[SharpFang]

There is one serious problem with sending robots there.
All the old BOFH jokes about cosmic rays? It's all true in there.
High radiation levels make bits skip like crazy in high-density memory and CPUs. Your parrot drone's firmware would crash within a mile of the power plant, unless you shield the CPU with enough lead so that it would never take off.

Then try to drive that remotely. The name "radioactivity" is not there in vain. It really creates horrible noise in all radio frequencies, so forget "fly by radio" models. Either it's autonomous, or driven by cable, or you set up a goddamned 100KW radio tower for driving your drone to overcome all the noise.

And then you got a ground drone with all electronics shielded by an inch of lead, driven by a mile long spool of cable unwound from a roll on the back. Now give it a camera that can still see the outside and won't crash due to radiation - possibly analog, with only the CCD exposed, and in such a way that radiation won't pass inside bypassing the lenses. Give it a manipulator arm that has all electronics shielded. Give it a battery that will be able to drive the half a ton of lead, 100kg of wire, and another half a ton of hardware of the device - forget your fancy micro engines, every exposed part must be thick rugged so that electric noise doesn't affect it. Make sure it's radiation-leak proof, because even a small hole in the shield may crash the software.

And now build it. How long will it take you to do it?

Re:Trivia

[Ruie]

After the Chernobyl accident, the team that had created the Lunokhod rovers was asked to build remote-controlled vehicles (RCV) to help clean up. The RCV's first task was to remove reactor debris (chunks of graphite from the core) from a roof, by pushing it off the edge of the roof. The RCVs worked well; eventually though they failed due to the radiation. This despite them being rad-hardened, as the original Lunokhods had been powered by an RTG.

RTGs do not produce much external radiation - they are based on alpha-emitter material that is absorbed by the surrounding shielding converting radiation into heat. However, space hardware is rad-hardened because of cosmic rays - natural radiation present in space. This is often not as high-level as can be found near reactor core.

Here is an interesting description of using a robot to fix a high intensity radiaiton source [physorg.com].