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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

nojayuk Re:Pick your units of radiation... (190 comments)

Ten trillion nuclear disintegrations of potassium-40 occur in a cubic kilometre of seawater every second. A single nuclear disintegration per second is a becquerel (Bq). Usually Bq are qualified by being associated with a mass or volume, Bq/litre or Bq/kg. Radioactivity in seawater is usually measured in terms of litres but if you make the sample size big enough (cubic kilometres) the numbers can look really scary.

about a month ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

nojayuk Re:Pick your units of radiation... (190 comments)

A cubic kilometre of seawater contains about 10 trillion becquerels of the naturally-occurring potassium K-40 isotope. That's ten fucking disasters per cubic kilometre using your scale and there's a lot of seawater on this planet (1.3 billion cubic kilometres according to most sources).

about a month ago
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Germany's Glut of Electricity Causing Prices To Plummet

nojayuk Re:Aluminium (365 comments)

Modern nuclear reactors can load-follow quite well, swinging output by 30% in fifteen minutes thanks to newer control tech and a lot of operational experience over the past 50 years. Load-following can even be done somewhat with older second-generation LWR plants. It's not actually done much since baseload nuclear power is very cheap in terms of fuel consumption and refuelling tends to be done at fixed intervals anyway. Other thermal generators like gas where the fuel is a major part of the cost of operations are normally used to top-up baseload stations -- in the UK the nuclear generators run full-out as much as possible with gas filling in much of the rest and coal as a cheap backstop, limited by pollution and carbon controls.

about 2 months ago
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Germany's Glut of Electricity Causing Prices To Plummet

nojayuk Re:Aluminium (365 comments)

Most renewable generators get a guaranteed minimum payment for electricity they feed into the grid (in the UK where I live windfarm operators get about £145 per MWh) so the "excess" production is not free, it is paid for by the grid operators and ultimately the consumers even if it is not needed sometimes. If the renewable generators stored their excess production and dispatched it into the grid at times of low output that would be a different story, but that would cost them money so they don't do that. The round-trip efficiency losses are even more reason for them not to build storage into their operations.

about 2 months ago
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Germany's Glut of Electricity Causing Prices To Plummet

nojayuk Re:Aluminium (365 comments)

Storage costs money. Lots of storage costs lots of money. Storage wastes energy too -- pumped hydro, the cheapest form of bulk energy storage has an input-to-output efficiency of about 65 percent. Baseload coal, gas and nuclear generation doesn't need storage to be useful and meet demand 24/7/365 unlike intermittent renewable generating capacity, but no-one ever adds the cost of storage to the cost of renewables when comparing prices.

about 2 months ago
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Why China Is Worried About Japan's Plutonium Stocks

nojayuk Re:Serously? (398 comments)

You mean like the major Japanese Army command centre in Hiroshima? Or the extensive Naval dockyards and repair facilities in Nagasaki, close to where the Allied invasion was going to hit the beaches in Kyushu? Nagasaki was actually a secondary target due to bad weather over the primary target, a place called Kokura Arsenal which might give you an idea why it was on the target list.

In reality the atomic bombs were used because they were ready to be used, just one more wonder weapon in a war filled with wonder weapons. They contributed to the decision by the Japanese War Party, the military/political group in power at the time, to surrender but it was mostly down to the Russians declaring war on Japan on the 9th of August 1945 and promptly destroying the last major Japanese army outside Japan itself, the million plus Manchurian occupation force with embarrassing ease.

about 2 months ago
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Chinese-Built Cars Are Coming To the US Next Year

nojayuk Re:Early days of KIA repeated (431 comments)

Diesel engines typically run at twice the compression ratio of a gasoline/petrol engine. They also last a lot longer than petrol engines in my experience. This may be because they are designed to deal with the higher compression and greater loads on crankshaft bearings etc. from day one. They do tend to be heavier than gasoline engines of the same power and torque though.

about 2 months ago
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MIT Used Lobbying, Influence To Restore Nuclear Fusion Dream

nojayuk Re:MIT sure has fallen far (135 comments)

ITER is not run by Americans so it is, de facto, poorly managed.

about 2 months ago
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B-52 Gets First Full IT Upgrade Since 1961

nojayuk Re:I wonder (190 comments)

A Korean comics artist name of Anyan does a web manga with anthropomorphic representations of military aircraft as high school girls. Tu-95 is very inquisitive, always sticking her nose in other people's business and always surprised that folks notice her doing it because of the racket she makes.

http://www.batoto.net/read/_/1...

about 3 months ago
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B-52 Gets First Full IT Upgrade Since 1961

nojayuk Re:I wonder (190 comments)

A couple of Tu-95 Bears flew down towards the north of Scotland a few weeks back, the RAF went up to welcome them outside the national limit and got some nice pictures. I grabbed them off the MoD website and bundled them up since most of my friends are Apple fans and don't do Flash.

https://www.mediafire.com/?fs5...

Runs to about 12MB or so as a zip download.

about 3 months ago
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Japanese Court Rules Against Restarting Ohi Reactors

nojayuk Re:Godzilla! (75 comments)

Actually the Japanese are burning more LNG with some extra coal to replace some of their nuclear generating capacity. In the 12 months up to March 2013 TEPCO burned 23 million tonnes of LNG and 7 million tonnes of coal to generate electricity, in comparison in the same period ending March 2011, just after the earthquake and tsunami they burned 19.5 million tonnes of LNG and 3.5 million tonnes of coal. LNG has twice the energy of coal tonne for tonne.

http://www.tepco.co.jp/en/news...

As for coal as a long-term solution the Germans plan to be still generating at least 40% of their electricity from coal and lignite by 2050. That seems quite long-term to me. I doubt very much the US will have stopped mining coal in South Dakota and West Virginia to burn in power stations by then either. The Japanese don't have any significant amounts of native coal left to burn, no oil and no gas so they have to import it. Uranium is cheap, their nuclear generating plants are still in place ready to restart and their balance of payments are in the crapper for the 22nd month in a row mostly due to buying carbon instead.

about 3 months ago
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US Officials Cut Estimate of Recoverable Monterey Shale Oil By 96%

nojayuk Re:Keystone XL (411 comments)

Which refineries in the north? The Texas and Gulf refineries have underutilised capacity especially for the heavy form of oil that is the end product of the Athabasca tarsands production. That's why the producers want to pipe it across America north to south, it's cheaper than building new refineries in Canada and it guarantees jobs and profits for US-based operations.

As for shipping the refinery product to Europe or China, if the US consumers are willing to pay the going price for the refinery output then it will sell in America. If other folks abroad are willing to pay more even with the shipping costs well that's capitalism for you, you know, free movement of goods and materials, one of the lynchpins of an unregulated market.

Of course you do realise that the Athabasca reserves are not American property but in fact the product of a foreign country being imported to the US, that free market capitalism at work? Why should the end result of processing foreign oil be reserved to subsidise US consumers when the source material is imported?

about 3 months ago
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Rising Sea Level Could Put East Coast Nuclear Plants At Risk

nojayuk Re:obsolete (323 comments)

you're lying, or maybe you're just ignorant or you got your "information" from bullshit anti-nuclear blogs and such, but...

a) nuclear power reactors are decommissioned to "greenfield" status, that is the land is fit to grow crops on afterwards. It's a lot more work than brownfield where the ground will be repurposed for industry but it's a cost the nuclear industry has to bear unlike, say, coal mining.

No a nuclear site doesn't need to be quarantined for "hundreds of years". Heck, even after Chernobyl burned its core to the atmosphere the other three reactors on the site were kept in operation. No quarantine.

Storm surges affect ex-nuclear sites in the same way they affect farmland since they present the same levels of threats of toxicity. If you're really worried about flooding then look to coal mines and coal power stations which regularly dump millions of tonnes of poisonous effluent into streams and drinking water after flooding takes out their inadequate levees and dykes. Nobody cares much though because it's not scary radioactivity.

As for the British SafeStor decommissioning system, it's an alternative method to prompt disassembly of a power reactor -- tear down everything around the containment since it's not radioactive and then wait about 60 to 80 years for the remaining radioactivity in the pressure vessel and surrounding structures to decay to the point where it can be dismantled with minimal precautions. Other countries deal with this differently, in the US the reactor vessel is usually extracted promptly and put in a pit to "cool down" for about the same length of time so the entire site can be cleared more quickly.

about 3 months ago
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Fujitsu Is Growing Radiation-Free Lettuce In Japan's Fukushima Prefecture

nojayuk Re:Yeah... (146 comments)

They're not using any pesticides or herbicides as they would have to in the "wild". There are no caterpillars, no fungus or microbial antagonists or weed seeds that could destroy or deplete the crop, they're kept at bay because the facility is a clean-room setup with filtered air and water. That's the big "no chemicals" deal with this greenhouse.

about 3 months ago
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H.R. Giger, Alien Artist and Designer, Dead at Age 74

nojayuk Re:Oh... and (92 comments)

Chris Foss is still around, in fact he's Artist Guest of Honour at this year's Worldcon in London.

about 3 months ago
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Percentage of Elderly In Japan Continues to Grow as Number of Children Drops

nojayuk Re:You real what you sow (283 comments)

Plenty of countries don't offer automatic citizenship to people who marry one of their citizens. The US doesn't, for example. They don't offer green cards or right of residence automatically either. Friends of mine who got married in the UK tried to move to the US where the wife was a natural-born citizen but her British husband was refused leave to stay. They lived in the UK for several years and finally after many appeals her husband managed to get a green card and they moved to the US. As far as I know he still hasn't got citizenship, I don't know if he's applied for it.

I know a few non-Japanese who are long-stay residents of Tokyo and environs. One is married to a Japanese woman and another has been engaged to a Japanese woman in the past but as far as I know neither wants citizenship.

about 3 months ago
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NASA, France Skeptical of SpaceX Reusable Rocket Project

nojayuk Re:Just because... (333 comments)

Works for me though. The RD-171 mounts to the bottom of the Zenit launcher as a single unit and gimbals as a single unit so I'd call it a single motor. The derivative RD-180 (half the number of combustion chambers, powers the Altas V series of boosters) is again a single motor. Like I said, some folks and especially Americans don't like the idea that the Rockwell F-1 wasn't the most powerful motor ever to fly and will attempt to weasel out of the facts.

And "beloved"? Uh, no. I may be strange but I'm not that strange. I do know people who have rocket engines in their garage though. The only bits I've got even remotely like that are some solar cells that fell off the back of a satellite.

about 3 months ago
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NASA, France Skeptical of SpaceX Reusable Rocket Project

nojayuk Re:Just because... (333 comments)

They've still got the cheapest launcher on the market,

The cheapest commercial launcher in the Falcon 9 capability range is the Indian GSLV but it has a poor track record. The ESA's Vega is cheaper per launch to orbit but with smaller payloads, as is the JAXA Epsilon. SpaceX has a bigger promotional budget though.

about 3 months ago
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NASA, France Skeptical of SpaceX Reusable Rocket Project

nojayuk Re:Just because... (333 comments)

One fuel and oxidiser inlet into one turbo pump equals one engine. It had four combustion chambers but no redundancy or any way of shutting off a single chamber if something failed upstream. More thrust than the F-1 even in its later form and a lot more efficient in terms of Isp. It's a great bar bet, "what's the most powerful rocket motor ever flown?" but getting Americans to admit the F-1 was number 2 in the list is always a pain as they try to weasel out of it.

about 3 months ago
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NASA, France Skeptical of SpaceX Reusable Rocket Project

nojayuk Re:Just because... (333 comments)

There have been several new launcher motors developed over the past decade (Vega and Epsilon, for example)

I thought both of these were simple solid-fuel designs?

Simple and cheap, both costing less to put a small payload into orbit than SpaceX charges and with lower overheads. The first Epsilon flew with only eight people controlling the launch and there was no launchpad fuel handling etc. needed. I don't know how much a Falcon-9-scale solid fuel launcher would cost to develop and produce though.

Another modern engine design I forgot to mention is the Japanese LE-7 LH2/LOX motor used on the H-2 series launchers. Very good Isp figures, significantly better than Merlin but a lot more expensive and non-recoverable.

about 3 months ago

Submissions

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First World to Third World

nojayuk nojayuk writes  |  more than 3 years ago

nojayuk (567177) writes "The nuclear plants in Japan damaged by the earthquake and tsunami are being stabilised after much drama and attention from the rest of the world, but there's another crisis approaching for the Japanese people, a severe lack of electrical power supply over the coming hot summer when air-conditioning loads will soar beyond the ability of the crippled electrical supply system.

  Pachiguy, the blogger at Spike Japan puts some numbers to the missing megawatts and the problems one of the world's most advanced countries in the world faces in keeping its people cool and its factories running over the next few years."

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