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Comment Re:central storage or n^x security guard costs / s (Score 1) 191

It releases more radioactivity each year in the form of radium (alone) than several chernobyls. There are a bunch of other nasties in there and as others have mentioned a bunch of heavy metals, etc.

Most of the elevated mercury levels in the world's oceans over the last 150 years is from coal burning, as a f'instance, not chemical releases.

We're very good at ignoring what we can't see but is dangerous and demonising stuff with low risk that has high impact (the fear of flying thing - you're more likely to die in a car crash on the way to the airport than to be injured in an aircraft)

Comment Re:central storage or n^x security guard costs / s (Score 2) 191

"I'm not so worried about low-level nuclear waste, but high-level nuclear waste is deadly for many multiples of human recorded history into the future. "

Please stop drinking the koolaid.

Contrary to popular belief, plutonium and uranium aren't particularly radioactive unless you put a lot of the pure stuff in a small enough space for the atoms to start affecting each other and give them a bit of assistance by arranging things "just right". The greater danger is chemical - they're both highly reactive and highly carcinogenic heavy metals (depleted uranium shells are decidely _non_ radioactive. They kill tank crews more by incineration than by kinetic energy, once they get through the armour and that chemical toxicity means they will leave a nasty legacy where used for decades to come)

"spent" fuel rods are blazingly radioactive thanks to high levels of calcium, cobalt and other unstable isotopes (handling one will kill you from the gamma exposure in very short order)

However: stick 'em in a safe place for 300-400 years and that gamma emission level will have dropped to a level low enough that the rods are safe to handle without requiring special kit - and once the contents are chemically processed, they can be reused as reactor fuel (enough plutonium in them to offset the near-natural uranium balance.

If you don't want to wait that long, just dump it all into a MSR and things will be "burned down" much more quickly - the big "positive" is that given the thorium cycle's calculated efficiency, you should be able to achieve 97-98% usage of the starting fuel, instead of 1%, so the amount of "hot stuff" coming out the other side is minimal _and_ shortlived. It's better to keep "hot" stuff in the reactor and extract the heat as work than it is to dump them in the bottom of a pool and let it heat the water.

MSRs are really good at producing heat and lousy at producing plutonium (it can be done, but it's a LOT harder than any uranium/water setup), plus they don't need massive cooling (they run much hotter than traditional plants, so thermodynamic efficiency is better), can't burp gasses, melt down or explode (the nuclear side is all unpressurised) - and the lack of water in the nuclear loop means they can't leak thousands of gallons of low-level contaminated water either. That makes them a far "safer" system from actual risk point of view.

http://en.wikipedia.org/wiki/M...

The steam turbine side comes with the usual issues of steam plants, but that can be entirely decoupled from the reactor itself (it's entirely possible to use sterling engines or thermocouples too) and any steam explosion is just that - a steam explosion

The fact that you can get hot side temps of 700-1400C means that the heat can be used directly in various industrial processes (eg: at ~1200C, water can be cracked to produce hydrogen, then air + plain old Haber–Bosch methods make ammonia from that and end products range from plastics to fertilizer).

Guard those "waste" piles well. They will be useful in the future.

Comment Re:central storage or n^x security guard costs / s (Score 1) 191

As with the USA, the problem sites in other countries are predominately military.

There's a coral reef in the mid pacific with several kg of plutonium powder scattered across it. The same location is leaking high-level radionuclides into the water at a depth of a few hundred metres, which are being picked up by currents and are detectable at other islands hundred of km away (volcanic seamounts are basically giant piles of sand)

It would have been safer for the French govt to run its nuke tests in an area with a nice solid deep basalt base - like under the Pyranees, but it was politically expedient to do it in the middle of nowhere and play fast/loose with the health of workers where noone could see and pesky protesters could be kept at bay by sticking a limpet mine on one of their boats in a nearby foreign country.

Comment Re:central storage or n^x security guard costs / s (Score 1) 191

"Or you do what everyone is actually doing, and using gas peakers in those periods."

At some point in the not-too-distant future those are going to be so heavily regulated and taxed that nuclear will be cheaper.

Bear in mind that even the old BWR plants are throttlable (they run at full power for economic reasons, not technical) and the MSR processes were shown to be highly throttlable (5 minutes or less) before Nixon forced the test rig to be shut down.

Assuming that Thorium MSRs take off (and I think that's a pretty safe assumption given the amount of money China's putting into them), the "waste nuclear fuel" problem won't be around for more than 50 years after they become mainstream power sources and most of the rest of the issue is "hot" but shortlived material with a dangerous lifespan of 2-300 years at most.

There are a number of areas with similar background radiation levels to Chernobyl and Denver has far higher background ionising radiation levels than Fukushima simply by being at altitude. If ionising radiation was a dangerous as some of the scaremongers insist, the average lifespan of airline pilots and cabin crew would be down in the 40s, not "no different from the general population" (Fallacy #1 is that radiation exposure is cumulative over your lifespan.)

Comment Re:Surprise? (Score 1) 579

"and especially so for power users of Excel"

I know what happens to organisations which rely on "power users of excel" - like the hospital which ran its financial systems on it and ended up several million dollars out of kilter.

Spreadsheets are for simple things. If you need a power user to achieve something with them, then you're using that hammer to bang in screws.

Comment Re: Surprise? (Score 1) 579

Have you ever tried to work with business-class documents using Word?

Just for shits and giggles: Save your file as a doc (or docx if you insist, but you'll need to gunzip it before proceeding to the next step)

rename the saved file from .DOC to .TXT

Reopen the file and be amazed at the crapola in there.

Just because word is ubiquitous doesn't mean it's _good_.

Speaking as a long-time GUI hater, I find Libre a lot easier to work with than MS Office

Comment Re:Do the math (Score 1) 338

3.7kW might seem insane, but if you look closely many of these are only 350-500 "air watts" - the rest is expended pushing air through HEPA filters.

There are better ways of handling things - external machines (house vac systems) which vent outside don't need to be nearly as high powered, nor do systems which vent the exhaust back down to the suction head - and as a nice side effect they don't spray nanoparticles into the air which invariably end up being inhaled.

Recirculating air in vacuum cleaners might seem logical, but EU and US patents for it (concept and implementation) was only issued in the last 15 years - and the early USA patents are not aimed at improving efficiency of cleaning or reducing power consumption.

http://www.g0cwt.co.uk/arc/ is worth a look

Comment Re:Do the math (Score 1) 338

Partly it's down to amps - the heating effect of current is the same no matter what the supply voltage might be, but if you're pushing 120V, you need ~twice the current for the same power as you do with 230V (and at 120V the wiring losses are more cirtical than at 230V as a percentage of total available power.)

The choices are to keep the current rating the same, or fit fatter wiring - which costs more.

The other part is that american wiring standards - to be blunt - are dangerously lax, with attendant higher risk of wiring fires (electrocution risk doesn't come into it - it only takes 150mA to kill someone. Fuses are to protect against fires). As such, insurance companies are more paranoid and mandate separate circuits for high power devices.

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