@Sarah Bee

"You can't possibly argue it on aesthetics. Cooling towers are uglier than your mum."

I quite like the shape. They same quite graceful. But they could do with a paint job.

"Cooling towers are uglier than your mum."

This I'm not so sure about.

@Andydaws

"A thorium-u233 makes roughly the same quantities of waste as a "classic" u 238-Pu239/240 cycle - thorium protagonists have a nasty habit of failing to compare like with like - they compare a "once through" cycle for uranium fuelled plant with a recycling-based approach for the thorium plant."

What *kind* of molten salt reactor are you talking about?

Molten salt fueled/cooled or molten salt moderated? AFAIK the Gen IV "Molten Salt" proposal just uses a molten salt as a coolant with all the usual paraphernalia of a conventional reactor.

I'll declare my hand - I think the Thorium-U233 cycle has potential

I'm glad you made that clear. It's pretty well hidden otherwise.

Let's be clear - making a thorium cycle work is hard, even if you use a throrium cycle in "conventional" (and that's stretching the normal use of the word) fast reactors.

True. The MSRE did *not* incorporate breeding of Thorium.

"More usually, the enthusiasts go further - they argue for a cycle based on thermal breeding in a molten-salt system."

Not to do so eliminates some of the *key* advantages of a molten salt reactor (IE one where the salt is both coolant and *fuel*).

"The neutron economy of such a system is utterly marginal - a 1% variation in the ability to extract fission products from the salt makes the difference between it producing surplus fuel, and needing continual top-ups."

The key one of which seems to be Xe135. The ability to purge the reactor of this was *the* key reason for designing a molten salt reactor (as part of the nuclear powered bomber programme) in the first place. And AFAIK the MSRE did *not* require top ups of Uranium. However as it did not including the breeding function this merely says a non breeder can be designed well enough *not* to need a top up.

"Worse, making a molten salt system works requires, a large scale and complex chemical processing plant to be added on to a reactor. A Molten Salt Breeder Reactor (MSBR) won't work if you let just a few percent of the siffion products (like Xenon) stay in the fuel - you need 95% plus efficient extraction on every circuit of the fuel."

I looked for "siffion" products but found nothing so I'll assume you mean fission products.

MSRE indicated both Xe and Kr poisons could be efficiently stripped by spraying the salt in a small chamber with an atmosphere of Helium. Both came *readily* out of the salt mix for later absorption onto carbon bed filters to be retained till their decay products could be released into the atmosphere.

" Worse, you HAVE to get out 90% or more of the intermediate between thorium and uranium on every cycle - protactinium. And to get that out will involve delights like passing 800C flouride-uranium salts through a column of molten bismuth, then extracting the protactinium frojm the bismuth somehow."

AFAIK already worked out. The description I'm aware of was a 1GW station would need A 4m (14 feet) high column. my experience of the chemical industry is that a 14 foot high column at probably a few atm (I'd expect it to operate near the same pressure as the core) is not *that* big a deal *despite* the temperature, which I would expect to be *lower* than the core in any case. This hardly compare to reactors for Ammonia or Nitric acid, typically running at 300-400atm, c300c and maybe 8-12 feet wide and 50-100feet high.

"Here's one for the enthusiasts - once the uranium is "bred" in the fuel/salt mixture (and leaving aside the delights of managing two such circuits, one for the fuel, and one for the breeder blanket), you have to get it out."

This *is* a reasonable concern and something which has not been demonstrated.Its complexity is the reason the MSRE did not include the breeding process. *However* the separation process is *well* understood using a combination of adding fluorine and distillation, *provided* you do have 2 separate circuits. The unavailability of a material with sufficient hot strength and chemical and radiation resistance at the preferred temperature was what stopped the MSRE testing this. Metallurgy has improved a bit in 40 years.

" And to do that, you have to bubble fluorine - that well known non-reactive and benign gas - through that same 800C molten uranium salt, then capture the resulting uranium hexaflouride. "Hex" is not only "hot" both thermally, and radiologically, but it's venomously corrosive - the separation membranes in enrichment plants have to be made of pure (99.9% plus) nickel to withstand it, and even then last only a few years."

As you point out this is *known* technology from the Uranium enrichment industry. Agressive certainly but *well* within the state of the art. Note also the "freeze valves" developed for MSRE would allow parallel processing columns (if needed) to be isolated for maintenance and replacement

And yes, it has virtues - thorium abundance, and potentially, it can be "drained down" in an accident. Bit that still means you have to remove decay heat from a couple of thousand tonnes of fuel mixture (more than in a conventional reactor), and have secure cooling and storage for the chemical plant and fission product inventory.

I'd doubt that. The MSRE salt mix density was 2300 Kg/m^3. Given that's lower than Aluminum and the *entire* volume of the MSRE (with no space taken up by the actual graphite moderator) would come to about 5500 Kg, with a maximum thermal output of 8MW I'd say 100x bigger would give c550 tonnes, so a 1GW (common size of power plant) reactor would have to be *very* badly designed to need more than a 1000 tonnes of salt .

As I said, it might have potential - but compared to something like a lead-cooled fast reactor, which have already been built in considerable numbers - the Soviets used them to power the "Alfa" class subs - doesn it look like an obvious route? Hardly...

You are aware that the design you're describing actually uses a lead/*bismuth* alloy?

It's major features being an ability to operate with natural convection in a "stealth" mode which is handy on a naval submarine. and will fail "badly" if the coolant freezes in the tubes.It's got *all* the issues conventional reactors have with fuel element design/certifcation and Xe135 and Kr reactor poisons, *without* the ability to irradiate decay products to *much* shorter lived elements, possibly *the* key benefit of this design if you want to have a nuclear fuel *cycle* instead of the burn/store arrangements most countries seem to have at present.

On the subject of the Alpha reactors for re-processing didn't the USSR just *dump* the cores at the end of life?

I'm not arguing, merely commenting that the phrase "Molten salt reactor" if used loosely has more than 1 meaning.

In case you haven't seen it this is the description of the work written by one of the team shortly after the MSRE. worth reading for the good, the bad and the could have been better.

www.energyfromthorium.com/pdf/NAT_MSREexperience.pdf

@Gilber Wham

"My Brothers-in-Law, both doctors, have been making this point for bloody years. It's all very well going private for elective surgery, but if you've got something seriously wrong with you, all they'll do is pay to use the NHS's resources to fix you anyway."

And in the case of BUPA if they f**k up your operation they'll dump you back at the nearest NHS hospital and won't pay a penny to any work they have to do.

At least that was their position some time ago. I'd *love* to know if they still play that game.

AC@15:32

A sort of department for the random killing of bureaucrats perhaps?

AC@01:16

Joking aside you make some valid points.

"They've been stagnating for coming on 30 years now. That tech hasn't much improved and hasn't become more reliable and hasn't made flying to space all that easier."

Actually it has not been *seriously* updated since it was designed. There have been individual *subsystem* tweaks (some pretty expensive) but the *real* game changers need wholesale changes, a budget to make them and a management prepared to take the *risk* that they *might* fail (although there is a *lot* than can be done to dry run those changes before being actioned). Possibly the *biggest* issue was they'd have to certify the design from scratch again.

" The fscking blue prints aren't even in metric."

And (certainly for the main engines) they still *are* blueprints (and microfiche). No neat CAD files that can be piped into a CFD programme to test out improvements.

"The poor things should've been put out of our misery 20 years back"

NASA has tried this on *several* occasions. Their last serious outing was in the early 90s and called the X33. It transferred $1.1Bn to LockMart and resulted in *no* flight vehicle.

LockMart had an expendable rocket business and made *much* bigger investment promises (concerning the planned "commercial" vehicle that would have been *derived* from X33) than its competitors, who would have become *new* competitors had they won.

It hoovered up the cash and, eliminated any *real* competition so that 20 years later it still launches payloads on very expensive expendable rockets. "So sorry. Who knew how hard it would be to do? Come back when you've got a bit more money to try again"

Right out of the Dick Jones management play book.

"Where is the replacement shuttle?"

See above.

"One with less parts, if that's the way to make it more reliable, cheaper, and quicker to run again."

That's certainly *one* of the ways to do it. There are at least *several* NASA studies on how to make a better shuttle, or even how to just re-implement the *architecture* better. Cutting down the number of separate fluids (and grades of fluid) would also help a lot.

" Recall that this vehicle was to be re-usable. It is, after a fashion. "

Refurbishable is *much* nearer the mark. Reusable sort of implies a wipe down and refilling the tanks (on the current design there are around 60 of them, many doing non obvious things).

"It's not efficient, not economical, not easy to launch, and a whole host of other things it also isn't. "Useful", for one.

Actually it has its uses. It is the only *US* vehicle *allowed* to carry crew to the ISS, and it's full payload of c55 000lb is at the *top* end of launch vehicles.

"_The Spirit of St. Louis_ did a, for that time, unimaginably big thing. But you can't run an airline service with it."

"Poor counters to the observation that we're still stuck with the "we can go into space with a lot of trouble, maybe, if the celestial AND earthly weather's just right" age and -mindset."

Note that is a US centric mind set. The Russians have launched in near gales. BTW despite it's c$6Bn price tag the Shuttle is not certified for instrument landings so it's not just *perfect* weather at Kennedy for the takeoff, it's also perfect weather at the *emergency* landing sites and Kennedy in case anything goes wrong. It's gotten a bit better about high altitude winds (they can hit 100Knots) due to revised control constants uploaded to the flight software about 2 hrs before flight.

NASA has been traditionally about 2 things. Performance uber alles and being both customer *and* major contractor. This has lead to designs that are *fragile* (especially when some of their suppliers don't deliver on their specs, as happened with both SSME and the solid fuel boosters on the Shuttle) and designs chopped and changed to meet the (set yearly) NASA budget, stretching out say a 3 yr programme to a 5 yr programme.

"As the odds would inexplicably have it, I am one of the seven billion odd minus 7 other people."

Only if you assume that the only way in to space is on a vehicle designed and partly built by the US government. That position is no longer true.

You're quite correct if you think that most of the "reasons" why space travel is *so* expensive sound like excuses it's because they *are*.

There has been *very* little competition in space launch. Note BTW that *no* existing US supplier has looked at offering transport to the ISS. Only the Russians (who needed the money) did not see anything *inherently* bad about the idea of space tourism.

It has taken a complete outsider from the hotel business (Robert Bigelow) to actually start *building* an orbital hotel, having acquired the core technology from NASA, who (along with Big Aerospace) managed to do *nothing* with it.

For a country that prides itself on being a classless society the US has probably the *most* elitist (and not in a good way) space programme on Earth.

That is *starting* to change.

Some parts of NASA are helping. Some parts (with substantial Congressional and Senate assistance) are (how to put this delicately) not.

Americans in space does not *have* to mean NASA, ex-test pilot or PhD.

Space is a place, not a programme.

I can't believe I missed the Rep Senator for Utah.

Home state of Thikol, the maker of the Shuttle SRBs and just about the worst location to set up a factory to produce a *large* solid fueled booster rocket *unless* you plan to launch on site.

His rabid support for the SLS and "Libety" concepts has been especially unimpressive.

No suggestion of a reasoned debate here.

More the Mayor in Robocop (without a request for a car that has really sh***y gas mileage).

A full blown pacifier ejection event in progress.

The Augustine commission noted that to carry out the Shrubs plan to return to the moon would take a *real* increase in the NASA budget (excluding inflation) of 50%. Their message to the Senate and the Congress was If you want to do this give them the *real* money necessary to do it or stop forcing them to look at it and keep working on it.

http://www.xcor.com/video/isdc.html

American readers might like to contact their relevant representatives (particularly their Congress people) and ask them why they are forcing NASA to continue to develop Ares (roughly 75% of the original budget) when they were asked *not* to by the president.

@Matt Bryant

"the territory of Northern Ireland was under British law UK Parliamentary control before the start of "the troubles" and remained so after the 1998 Agreement"

No. Roughly 1922-1972 Northern Ireland *was* a devolved government run from Stormont Castle, with a "Governor" rather more like Honk Kong but the people retained the right to elect MP's to the House of Commons. This was suspended in 1972 and direct rule from Westminster instituted. Rule from Stormont was re-instituted under different rules from 1998 onward.

"A simple comparison shows the Brits "won" as they restored order and prevented control of Northern Ireland falling into Southern Irish hands, whilst the IRA definately had to abandon their priciple objective "

Wrong. The Sein Fein still want a united Ireland. They have accepted that the merger would only happen if the *majority* on *both* sides of the border want it. BTW the referendum for the 1998 agreement took place on *both* sides of the border between NI and the Republic.

"That is much more relevant to the arguments saying that every Gitmo detainee will become a "dedicated terrorists" that will never accept defeat."

Read what I wrote, not what you think I wrote.

AC@13:37

MP's tipped off to hashish use by "Spc. Justin Stoner,"

Gotta love that.

Their other behavior was rather less amusing.

"forcibly sterilise the entire population of the world,"

The device for this is largish nuclear weapon with a Cobalt casing detonated in the jetstream.

I read about it at my HS in a book written in the late 50s.

IIRC it was estimated it would take 4.5 days to circle the Earth and Co60 has a half life of 5.4 years.

Co60 is a gamma ray emitter used to sterilize potatoes. It's effect on higher life forms was expected to be equally shriveling.

They called it a doomsday device.

I think you can see why.

@Tim Greenwood.

"years with full stripdown service with some renewal after 10 years) at 30-40% efficiency then their payback is pretty bloody crap. "

The Register has mentioned before that large wind generation companies work on the basis that a windmill will generate power 26% of the time (30% offshore)

However at least 1 site listed in an Andrew Orlwoski article was 1 wind mill showing 5% (roughly 19days a year) operating time.

The actual *electrical* generator is something like 96% efficient (when it's working of course).

A *full* accounting on "Green" energy would need to factor in *all* carbon emissions from the supply chain (For example until a few weeks ago *all* current UK windmill towers were made in China) *and* the carbon footprint of the *backup* system that will have to step in.

Sandtreader

Thank you for providing some actual statistics rather than just an opinion.

@Conrad Longmore

"Openreach exists to allow rival operators access to BT's infrastructure as part of an agreement with Ofcom. I would not be at all surprised if BT eventually spins Openreach off as a separate company (think National Grid for telecommunications)."

That should happened *long* ago.

As a division the sense that BT gets just that *little* bit better service when it's got its ISP hat on is hard to get rid of.

@Scarborough Dave

I'm thinking something a bit more general purpose.

1) Total fanbois *completely* under the control of Apple/Google/Linux/Microsoft/etc

2)User/site/company totally pwnd by virus/worm attack.

I give you the Gimp face mask from Pulp Fiction.

Distinctive.

Stood the test of time.

Leaves people in no doubt what you think of them.

@Keith T

Pinocchio is good.

Widely understood

Timeless.

@Dave Walker

"To open up the frontier the government, decades later, invested in the railroads which provided frequent, reliable, and sustainable round trip capacity."

I'm not sure the US Gov actually *invested* in the building of the railroads.

AFAIK they made land grants to deal with the *route* but otherwise the railroads were *privately* financed. I recall that it was the ownership of this transport network by a *very* few large families (Van der Bilts and Rockerfellers?) that meant they could dictate prices for things like transporting oil. Sure they'd *let* competitors transport their goods, but at rates which were extortionate, slowly strangling the competition.

IIRC it was one of the triggers for the first anti trust/monopoly laws being enacted in the US.

It's always wise to check that we recall history as it *was*, rather than how we would like it to have been based on c140 year difference in PoV.

@Matt Bryant

"Which all kinda neatly avoids the facf that the mainstream IRA eventually realised it could not win a protracted "war" with the UK and eventually settled for disarment and entry to the political system. "

You don't know much about the IRA's campaign or it's strategy.

Hint. It was known as "The Armorlite *and* the ballot box." "Disarmament" came a *long* time afterward. Nearly 2 *decades* after they tried to blow Margaret Thatcher into small pieces at Brighton and gave Norman Tebbit a steel plate in his head.

"So, obvioulsy, all those Irish "detainees" that you are convinced became life-long commited terrorists also accepted the solution ("

After they'd killed off a few 1000 men, women and children on both sides. Although in some cases I think some of the more extreme cases were put down by their own side in the end.

"(mustn't call it "defeat", the IRA sympathisers like to cling to the idea that they didn't "lose", despite their having failed to achieve any of their aims)."

another comment that show's your ignorance of the peace process.

As long as *no* one "won" everyone could get *part* of what they wanted. If someone *felt* they had won, everyone *else* would feel they had lost and it would all start again.

"It is illogical, but it is a fact" as Mr Spock would say.

"By that token, your argument is shown to be moot in the longrun."

Firstly it's not my argument. It's the analysis of the MoD based on 38 *years* of deployment.. Secondly it means that *not* interning a lot of people on *flimsy* evidence would have saved a *lot* of people they went on to kill and maim. It was also a knee jerk reaction that "Something *must* be done."

That does not make it moot. It makes it highly relevant.

I've noticed a certain vehemence in your posts which IRL i've seen from people who've either lost loved ones to terrorist incidents or lived with the *fear * of loosing them to such a situation. People who've lived *through* such incidents (I've only known one of those at second hand so my sample is limited) were just damm happy to still be alive.

That fear is expressed as a willingness to use unlimited levels of aggression and a complete abandonment of *any* sense of compassion or humanity towards their *perceived* enemy.

Are you supporting the US governments behaviour or trying to justify your own?

@Stratman

"Did I read that correctly? The Land of the Free imprisoned a FOURTEEN year old kidnap VICTIM to extract information from him?"

Correct.

I guess they figured that the idea a fourteen YO might be a bit traumatized by being seized at gunpoint and threatened with death was IDG some sort of liberal tree hugging hippy crap.

A touch of death metal or some good old waterboarding and he'd soon recover his memory.

Does that sound as mad to you as it does to me?

@andrew jones 2

Nice summary. I note this *appears* to be opt in.

It wold seem that the only way to scupper this idea (if your Android does not collect the info, every other user Android does) would be to for WiFi operators to randomly reset their hardware and invalidate data that was collected before a certain date.

Personally I have a router with wireless as an option. I keep it disabled.

That might not be an option for other people.

@Jared Hunt

"You might want to review your history too - Gagarin Flew in 1961. "

I stand corrected.

However NASA's formation in 1958 was partly (mostly?) triggered by the orbiting of Sputnik 1 in 1956. It started looking at ways to respond to this event *very* shortly afterward.

11 years from *no* successful launches to 2 men on the moon is still *very* impressive.

It's amazing what you can do *provided* money is *literally* no object.

I would maintain that Apollo's biggest legacy is that it *could* be done and the engineering data needed to tell future developers what you have to be able to *do* to repeat it.

*How* you meet those requirements determines if you can do it at an Apollo price tag or *considerably* cheaper.

@Rober E A Harvey

". For God's sake, from Gagarin to Apollo's landing was barely 9 years,"

You might like to review your history.

Gagarin orbits the Earth 1956

NASA formed 1958

Apollo lands on the Moon 1969

9 years would be 1965. which would be about the time of Gemini.

@Joe Cooper

"Yessir, but the atmosphere is about 1/100th the density."

I'd forgotten just *how* thin the Mars atmosphere is.

Re-read the article though and you realize it makes *no* mention of Dragons ability to make the entry, just that *if* it could the system they have got funding for will allow precision landing (yards, rather than fractions of a nautical mile).