That's the problem: regular ambient outdoor air is far more corrosive than indoor air (or better, an intentionally low moisture/low oxygen gas gap). And it's far worse if either the air is exposed to cooling tower mist or ocean air.
The reality is that steel vessels leak over time. Its what they do. And it's really, really dang hard to stop them. Whether you're talking about ships, water tanks, or yes, nuclear reactor containment structures. Who cares what pressure it's designed to handle when you have a Hole In The Side?
The AP1000 has no secondary containment vessel. It's a step backward. It's a single steel shell with a big tank of water over it. One layer. Lots of welds. In contact with corrosive air. Surrounded by a building which is, instead of trying contain releases, designed to encourage them them to vent (in order to help cool the shell).
Even with PV, which is generally more expensive than thermal, FirstSolar is producing cells for something like $0.75/W nowadays. Now, there's a lower capacity factor, and you still have installation costs, but still... that's it, your only costs. No relevant disaster liability, no fueling, no decommissioning, none of that. Just a tiny bit of regular maintenance.
Please point to where I said that the AP1000 uses graphite.
I assume I don't have to explain the meaning of "for example"?
no it isn't.
Yes, it is. It's a single-layer containment structure; there is no secondary containment. Quite the opposite, the outer shell is designed such that it would encourage the output of any fission products that escape primary containment. The inner shell is thicker than normal, but it's your only line of defense. And it's just plain steel -- with a huge number of welds (each weld being a potential point of failure) and surrounded by a shell that encourages convection of warm, high moisture air (or even salt air in seaside locations).
Corrosion has been a *huge* issue for nuclear reactors, and corrosion problems have been far more common than the NRC has ever predicted (and the record of lousy jobs being done on inspection... well, let's just say it's pretty bad). In this particular case, your main threat is damage like the Beaver Valley hole -- a hole that went right through the primary containment vessel between inspections and was found two years ago (which would be far worse in a design like the AP1000). Here you have a steel shell channelling oxygen and moisture-laden air up against the steel through areas that are difficult (and in some cases, outright impossible) to inspect, and to top it off? A giant steel tank of water overhead (have you ever seen an old water tank that *doesn't* at some point spring leaks and drip on what's below it?)
Overconfidence is always the greatest weakness of nuclear power plant designs, and I see it galore in a lot of the new designs like the AP1000.
Per-kilowatt I'm amazed at how expensive this is. $7/W just in construction costs? Yeah, I know nuclear has a higher capacity factor than wind and solar, but still... ouch.
And the article summary repeats the whole "passively cooled" thing as if that equals "safe".:P First off, it's not even a true passive system. The "passive" system must successfully activate within 30 minutes, and only works for 72 hours. It's only passive in that it doesn't require electricity once started, and assuming that it works properly. Secondly, "passive" does not automatically equal 'safe' anyway. For example, a number of graphite-moderated reactors have been declared "safe" because of a negative void coefficient, so if you lose your working fluid and air gets in, the reaction still slows down. Great, except that hot graphite *burns* or otherwise erodes (burning graphite is what spread the Chernobyl radiation).
In general, "passive safety" is an excuse to cut down on containment structures, which have saved our collective behinds many times over. And the AP1000 is no exception, with its bargain-basement containment design. I'm amazed that the construction cost on these is still this high despite the corner-cutting.
I'm not an expert on thermal imaging, but the paper that first discussed it was in 2001 and used AVHRR imaging. The lake apparently drains periodically and then refills later, but so do most "persistent" lava lakes.
In fact, there are very few places in the world (I believe it's seven) where there are exposed, persistent lava lakes. They're very rare. I believe the list is Erta Ale (Ethiopia); Nyiragongo (Congo); Erebus (Antarctica, offshore island) ; Saunders (South Sandwich Islands); Villarrica (Chile); Kilauea (Hawaii); and Marum (Vanuatu). It's one of my dreams to someday climb the volcano on Saunders and see the lava lake at the summit; as far as I am aware, nobody has ever done so (its existence is inferred from the presence of a persistent steam cloud and satellite thermal imaging, but it's a very remote, inhospitable location; to even get there, you have to charter an oceangoing yacht and do a difficult landing in an inflatable boat, timed to the waves, onto rocky cliffs, in the middle of the South Atlantic).
No, drilling into a magma chamber doesn't trigger an eruption. A tiny borehole isn't nearly enough of a weakness (remember also that it's not so much a "hole"; it's a tube full of "mud" with roughly the same density as the surrounding rock, so the pressure is equalized). They accidentally drilled into a magma chamber in Krafla (Iceland) at one point. The magma filled up the bottom couple dozen meters of the bore before semi-solidifying. Not sure what to do, they tried starting injecting water, and it actually worked; they're now producing steam from it and are considering drilling more such holes intentionally (they had previously tried to avoid the magma).
Thank you for that. The reality is, drivers of cars nowadays generally do get the advertised mileage. This wasn't true before the EPA standards were revised, but it is now. For example, concerning the Prius, compare the rated mileage with the average of real-world reports. Punch in any car you want there -- you'll find a surprisingly good correspondence.
And contrary what people have been saying elsewhere in this thread, hybrids are *not* only about "energy recapture". The energy recapture isn't even that efficient. What a hybrid lets you use is use a smaller, lower fuel consumption engine in the vehicle but still get the same sort of power output when you need it thanks to electric assist. The small engine is run harder, pushing it closer to peak efficiency. To pretend that doing this won't significantly increase the mileage is to pretend that big engines have the same fuel consumption as small engines. Beyond this, the best hybrids like the Prius and 1st gen Insight not only have hybrid drivetrains, but significant streamlining. Again, to pretend that aerodynamic drag is unimportant in terms of fuel consumption is pure idiocy. .
The reality is that hybrids *are* efficient vehicles. Now, you can be a hypermiler like me, add custom mods, and outperform your vehicle's rated numbers (my 1st-gen Insight's FCD currently reads 2.3L/100km (102mpg);) ) (I'll admit, that's a little extreme even for me!). But I have little doubt that if I drove it as stock and in a normal fashion, it'd get around the rated 48mpg city/60 hwy
Well, that depends on what you mean. If you mean storms, parts of northern Iceland are borderline desert, akin to New Mexico in amount of annual precipitation. Now, the southern coast on the other hand, chunks of it would be considered rain forest if they were forested;) There's a major rain shadow effect.
Iceland has excellent ports and regular shipping service which already takes lots of goods in and out, followed by a quick drive around Hringveginn. You're not going to drive things straight up to the destination in Norway, either -- you'd ship them to Trondheim and then drive them the rest of the way up the E6. Where, unlike Iceland, power, aluminum, and bandwidth are not in surplus.
Yeah, Antarctic buildings generally slowly sink/get buried; it's a big challenge. Bedrock is best.
I'm surprised that Iceland isn't more utilized. It's a first-world nation, the north/northeast has lots of areas that are borderline desert, it's pretty far north (Fairbanks-ish, further north than Yellowknife), the whole country is well connected by an excellent road system (except for parts of Vestfirðir), there's a very low population density (and thus low light pollution outside the capitol region), a huge amount of aluminum production (it's one of the main exports), and electrical power is abundant and cheap. Sounds like a good site for building large high-latitude telescopes, IMHO.
Well, the goal was a socialism-inspired production/distribution management system. Just like how DARPA had no clue what the internet could become, neither did Allende's people. But what they created clearly was headed down a direction that likewise could have led to not only the internet, but instant, true (non-representative) democracy. An awesome system.
Eh, pot smoking in Iceland doesn't seem any more common than anywhere else. But yeah, the sweater thing (lopapeysur) is pretty spot on -- you could have added "$80-200" to the list of descriptors as well;) Hagkaup (common chain of Icelandic grocery stores) even has an entire (sizeable) lopi yarn section. You can have your choice from dozens of types of lopi but can't buy headache medicine there;)
Well, there is an element of truth to it. When talking about Icelandic with people, I've frequently found myself making references such as, "... kind of like the Scottish word (blank)". Many of the settlers of Iceland came from viking settlements in Scotland and Ireland.
No, not just by rate of intake; there's a limit to how fast your body can convert it, regardless of how much you consume. Wikipedia has a nice referenced summary on it.
That said, even a low conversion efficiency of ALA to EPA and DHA doesn't necessarily mean that it's bad. One could argue that even a very DHA-rich fish, like atlantic salmon, is only about 3% DHA, while flax oil is ~55% ALA, and flax meal is around 2/3rds oil, so even a poor conversion rate still yields roughly similar amounts per unit mass of food consumed. But basically, there just aren't enough studies on whether ALA provides the same sort of benefits, and I hope that gets remedied soon.
From what I've read, it's not "as needed", but is rate-limited -- and that rate is different for individuals. And the studies I've seen on whether ALA input is useful in the same way as EPA and DHA -- studies which are limited in quantity -- have had mixed results.
BTW, do you grind your own flax seed? I strongly recommend it, since flax seed is more stable than flax meal, which is more stable in turn than flax oil (it's a shame that omega-3s are so fragile). All it takes is a coffee grinder.
It's been well established that trans fats are bad, but what I'm wondering about is the omega-3s. There's a lot of dispute over whether all omega-3s are healthy, or just EPA and DHA. That is, are ALA-rich foods like flax, hemp, nuts, etc providing a valuable nutrient, or just fat?
Contrary to many scare reports, lithium is not particularly rare or expensive -- under $10 a kilogram for lithium carbonate, which is used to make a dozen or two percent of the mass of batteries that sell for hundreds of dollars per kilogram. It's a couple percent of the cost. The main risk for lithium is temporary supply shortages, where demand outgrows production rates (it takes many years to get a new mine started). And of course, everyone wants to produce the cheapest stuff, but the cheapest stuff isn't always in the best of locations (producing from seawater -- a basically boundless supply -- costs ~$30 or so per kilogram of carbonate, versus a couple dollars per kilogram from a good lithium-rich playa.
It's not batteries that will be displaced by elevated lithium prices, but the other uses, which currently make up the vast majority of lithium consumption -- alloys, greases, glass, ceramics, etc.
Slashdot Mirror
That's the problem: regular ambient outdoor air is far more corrosive than indoor air (or better, an intentionally low moisture/low oxygen gas gap). And it's far worse if either the air is exposed to cooling tower mist or ocean air.
The reality is that steel vessels leak over time. Its what they do. And it's really, really dang hard to stop them. Whether you're talking about ships, water tanks, or yes, nuclear reactor containment structures. Who cares what pressure it's designed to handle when you have a Hole In The Side?
The AP1000 has no secondary containment vessel. It's a step backward. It's a single steel shell with a big tank of water over it. One layer. Lots of welds. In contact with corrosive air. Surrounded by a building which is, instead of trying contain releases, designed to encourage them them to vent (in order to help cool the shell).
$7/W doesn't sound that much to me
Even with PV, which is generally more expensive than thermal, FirstSolar is producing cells for something like $0.75/W nowadays. Now, there's a lower capacity factor, and you still have installation costs, but still... that's it, your only costs. No relevant disaster liability, no fueling, no decommissioning, none of that. Just a tiny bit of regular maintenance.
Please point to where I said that the AP1000 uses graphite.
I assume I don't have to explain the meaning of "for example"?
no it isn't.
Yes, it is. It's a single-layer containment structure; there is no secondary containment. Quite the opposite, the outer shell is designed such that it would encourage the output of any fission products that escape primary containment. The inner shell is thicker than normal, but it's your only line of defense. And it's just plain steel -- with a huge number of welds (each weld being a potential point of failure) and surrounded by a shell that encourages convection of warm, high moisture air (or even salt air in seaside locations).
Corrosion has been a *huge* issue for nuclear reactors, and corrosion problems have been far more common than the NRC has ever predicted (and the record of lousy jobs being done on inspection... well, let's just say it's pretty bad). In this particular case, your main threat is damage like the Beaver Valley hole -- a hole that went right through the primary containment vessel between inspections and was found two years ago (which would be far worse in a design like the AP1000). Here you have a steel shell channelling oxygen and moisture-laden air up against the steel through areas that are difficult (and in some cases, outright impossible) to inspect, and to top it off? A giant steel tank of water overhead (have you ever seen an old water tank that *doesn't* at some point spring leaks and drip on what's below it?)
Overconfidence is always the greatest weakness of nuclear power plant designs, and I see it galore in a lot of the new designs like the AP1000.
Per-kilowatt I'm amazed at how expensive this is. $7/W just in construction costs? Yeah, I know nuclear has a higher capacity factor than wind and solar, but still... ouch.
And the article summary repeats the whole "passively cooled" thing as if that equals "safe". :P First off, it's not even a true passive system. The "passive" system must successfully activate within 30 minutes, and only works for 72 hours. It's only passive in that it doesn't require electricity once started, and assuming that it works properly. Secondly, "passive" does not automatically equal 'safe' anyway. For example, a number of graphite-moderated reactors have been declared "safe" because of a negative void coefficient, so if you lose your working fluid and air gets in, the reaction still slows down. Great, except that hot graphite *burns* or otherwise erodes (burning graphite is what spread the Chernobyl radiation).
In general, "passive safety" is an excuse to cut down on containment structures, which have saved our collective behinds many times over. And the AP1000 is no exception, with its bargain-basement containment design. I'm amazed that the construction cost on these is still this high despite the corner-cutting.
... my data says that you can get a job working with FOSS in Iceland. Looking to move til klakkans? ;)
Seriously, though, it seems odd to me to hear that you've been having trouble finding ads for FOSS jobs; I never found them particularly rare at all.
Ah, is this going to turn into Estonia vs. the Nordics flamewar? The timing is great: this ;) Estonia is a recurring character there.
BTW: "Um Björk" would mean "About Björk" (or "about birch"). :)
No, that'd be "tík" ;)
BTW... björk simply means "birch".
I'm not an expert on thermal imaging, but the paper that first discussed it was in 2001 and used AVHRR imaging. The lake apparently drains periodically and then refills later, but so do most "persistent" lava lakes.
Here's the paper:
http://www.sciencedirect.com/science/article/pii/S0377027301002372
In fact, there are very few places in the world (I believe it's seven) where there are exposed, persistent lava lakes. They're very rare. I believe the list is Erta Ale (Ethiopia); Nyiragongo (Congo); Erebus (Antarctica, offshore island) ; Saunders (South Sandwich Islands); Villarrica (Chile); Kilauea (Hawaii); and Marum (Vanuatu). It's one of my dreams to someday climb the volcano on Saunders and see the lava lake at the summit; as far as I am aware, nobody has ever done so (its existence is inferred from the presence of a persistent steam cloud and satellite thermal imaging, but it's a very remote, inhospitable location; to even get there, you have to charter an oceangoing yacht and do a difficult landing in an inflatable boat, timed to the waves, onto rocky cliffs, in the middle of the South Atlantic).
No, drilling into a magma chamber doesn't trigger an eruption. A tiny borehole isn't nearly enough of a weakness (remember also that it's not so much a "hole"; it's a tube full of "mud" with roughly the same density as the surrounding rock, so the pressure is equalized). They accidentally drilled into a magma chamber in Krafla (Iceland) at one point. The magma filled up the bottom couple dozen meters of the bore before semi-solidifying. Not sure what to do, they tried starting injecting water, and it actually worked; they're now producing steam from it and are considering drilling more such holes intentionally (they had previously tried to avoid the magma).
Thank you for that. The reality is, drivers of cars nowadays generally do get the advertised mileage. This wasn't true before the EPA standards were revised, but it is now. For example, concerning the Prius, compare the rated mileage with the average of real-world reports. Punch in any car you want there -- you'll find a surprisingly good correspondence.
And contrary what people have been saying elsewhere in this thread, hybrids are *not* only about "energy recapture". The energy recapture isn't even that efficient. What a hybrid lets you use is use a smaller, lower fuel consumption engine in the vehicle but still get the same sort of power output when you need it thanks to electric assist. The small engine is run harder, pushing it closer to peak efficiency. To pretend that doing this won't significantly increase the mileage is to pretend that big engines have the same fuel consumption as small engines. Beyond this, the best hybrids like the Prius and 1st gen Insight not only have hybrid drivetrains, but significant streamlining. Again, to pretend that aerodynamic drag is unimportant in terms of fuel consumption is pure idiocy.
.
The reality is that hybrids *are* efficient vehicles. Now, you can be a hypermiler like me, add custom mods, and outperform your vehicle's rated numbers (my 1st-gen Insight's FCD currently reads 2.3L/100km (102mpg) ;) ) (I'll admit, that's a little extreme even for me!). But I have little doubt that if I drove it as stock and in a normal fashion, it'd get around the rated 48mpg city/60 hwy
Well, that depends on what you mean. If you mean storms, parts of northern Iceland are borderline desert, akin to New Mexico in amount of annual precipitation. Now, the southern coast on the other hand, chunks of it would be considered rain forest if they were forested ;) There's a major rain shadow effect.
Iceland has excellent ports and regular shipping service which already takes lots of goods in and out, followed by a quick drive around Hringveginn. You're not going to drive things straight up to the destination in Norway, either -- you'd ship them to Trondheim and then drive them the rest of the way up the E6. Where, unlike Iceland, power, aluminum, and bandwidth are not in surplus.
Yeah, Antarctic buildings generally slowly sink/get buried; it's a big challenge. Bedrock is best.
I'm surprised that Iceland isn't more utilized. It's a first-world nation, the north/northeast has lots of areas that are borderline desert, it's pretty far north (Fairbanks-ish, further north than Yellowknife), the whole country is well connected by an excellent road system (except for parts of Vestfirðir), there's a very low population density (and thus low light pollution outside the capitol region), a huge amount of aluminum production (it's one of the main exports), and electrical power is abundant and cheap. Sounds like a good site for building large high-latitude telescopes, IMHO.
Well, the goal was a socialism-inspired production/distribution management system. Just like how DARPA had no clue what the internet could become, neither did Allende's people. But what they created clearly was headed down a direction that likewise could have led to not only the internet, but instant, true (non-representative) democracy. An awesome system.
Eh, pot smoking in Iceland doesn't seem any more common than anywhere else. But yeah, the sweater thing (lopapeysur) is pretty spot on -- you could have added "$80-200" to the list of descriptors as well ;) Hagkaup (common chain of Icelandic grocery stores) even has an entire (sizeable) lopi yarn section. You can have your choice from dozens of types of lopi but can't buy headache medicine there ;)
Well, there is an element of truth to it. When talking about Icelandic with people, I've frequently found myself making references such as, "... kind of like the Scottish word (blank)". Many of the settlers of Iceland came from viking settlements in Scotland and Ireland.
No, not just by rate of intake; there's a limit to how fast your body can convert it, regardless of how much you consume. Wikipedia has a nice referenced summary on it.
That said, even a low conversion efficiency of ALA to EPA and DHA doesn't necessarily mean that it's bad. One could argue that even a very DHA-rich fish, like atlantic salmon, is only about 3% DHA, while flax oil is ~55% ALA, and flax meal is around 2/3rds oil, so even a poor conversion rate still yields roughly similar amounts per unit mass of food consumed. But basically, there just aren't enough studies on whether ALA provides the same sort of benefits, and I hope that gets remedied soon.
This whole app sounds like a modern rip-off of Salvador Allende's star-trek-ish proto-internet, Cybersyn
... who wants you to declare independence and try to be seen as a Nordic country.
Not that that would necessarily be a bad thing... ;)
From what I've read, it's not "as needed", but is rate-limited -- and that rate is different for individuals. And the studies I've seen on whether ALA input is useful in the same way as EPA and DHA -- studies which are limited in quantity -- have had mixed results.
BTW, do you grind your own flax seed? I strongly recommend it, since flax seed is more stable than flax meal, which is more stable in turn than flax oil (it's a shame that omega-3s are so fragile). All it takes is a coffee grinder.
It's been well established that trans fats are bad, but what I'm wondering about is the omega-3s. There's a lot of dispute over whether all omega-3s are healthy, or just EPA and DHA. That is, are ALA-rich foods like flax, hemp, nuts, etc providing a valuable nutrient, or just fat?
Contrary to many scare reports, lithium is not particularly rare or expensive -- under $10 a kilogram for lithium carbonate, which is used to make a dozen or two percent of the mass of batteries that sell for hundreds of dollars per kilogram. It's a couple percent of the cost. The main risk for lithium is temporary supply shortages, where demand outgrows production rates (it takes many years to get a new mine started). And of course, everyone wants to produce the cheapest stuff, but the cheapest stuff isn't always in the best of locations (producing from seawater -- a basically boundless supply -- costs ~$30 or so per kilogram of carbonate, versus a couple dollars per kilogram from a good lithium-rich playa.
It's not batteries that will be displaced by elevated lithium prices, but the other uses, which currently make up the vast majority of lithium consumption -- alloys, greases, glass, ceramics, etc.