/sci/ - Science & Math

Slightly radioactive steel cannot be used for certain sensitive instrumentation components or things near those instruments

i've always been curious about why the premise was impossible, the mosquitoes essentially took a blood sample correct?
>>5941167
i know about this but it would have worked otherwise right?
also i think it's more like a 25,000 year half life depending on temperature swings

>>5933949
you're talking about LENR which is still kind of dubious but nasa is sort of looking into it for possible validity
there's some strange stuff going on which we understand only poorly, neutrons being generated without any excess energy and immediately fusing with things nearby.
the "melting windows" thing happened to a small team working on this back in the pons&fleschman days, they let the little thing run for about a week and one day came back to the lab basically incinerated and the windows mildly melted from the heat. they nevere figured out what aspect of the reactor led to that.

in any case i trust nasa's word on this and absolutely nobody else.

depends on the type
magnetic confinement or inertial confinement? decades, maybe half a century

magnetized target fusion? maybe a little as 15 years, depends on how swimmingly the general fusion prototype goes

>>5870965
the hydrogen explosions weren't really that important in the whole series of events at fukushima, and they probably had to let that happen anyway.

the explosions didn't cause any damage to the important parts of the reactor, it just blew the rather fragile roof off, which is what it's supposed to do

but LWRs are still kinda iffy in scenarios like that.

>>5870509
the reactor is so incredibly neurton heavy that none of the really nasty long term stuff can stick around for very long, it gets kicked further up the periodic table until it gets so unstable it fissions down into the really short half-life waste products.

i believe if you build your reactor right, the longest half-life waste product is like 60 years? so it drops to background after about 300 years. Making a waste storage cask that can be bulletproof for 300 years is shit-easy compared to 10,000

fun fact; the potentially biggest problem with a lftr reactor is letting the fluorine gas escape.
the fuel salt will freeze to solid almost instantly if there's a hole in the primary loop, so no escape risks there
but the fluorine is really nasty shit

really, it's more like a chemical plant than a nuclear reactor

its an utterly alien technology to the current nuclear fission industry, which is incredibly starved for research funding (there almost isn't any at all). they're also quite paranoid about "new" stuff since they have every reason to fear gremlins in the system.

basically this means LFTR will propagate very slowly into energy policy unless it becomes an issue as big as gay marriage

>>5865443
>>5865366
you should probably actually read about graphene instead of just sticking it wherever you need (?mystery wonder material?)
the wiki page is a good place to start, lots of numbers

>>5861893
if i remember correctly, it doesn't use much fuel to land since it free-falls most of the time.

in any case, the money gained by getting your entire vehicle back more than covers the cost of fuel. best part is that newer (and better) maintenance techniques means they can give the whole rocket a once-over and replace ANY even SLIGHTLY defective parts within like a week or something, and be ready to launch again. that's pretty damn significant

spacex has done lots of neat, clever things to cut launch costs without compromising safety...
and this is probably the best one
of course its only been possible recently due to the falling cost, shrinking size and increasing precision of the required electronics
i look forward to seeing the first test of the full blown system, as well as some hard numbers about how much money this will save them

concerns about losing your fuel in a rocket accident and it spreading all over.

which is kind of unfounded, if it's atomized that stuff with spread basically everywhere.
and of course you'd be firing the actual fuel up on its OWN rocket in a VERY WELL SHIELDED re-entry pod that can survive a catastrophic rocket failure.
and once it's in space, the reactor needs to be very well shielded as well as detachable for exactly these reasons.

even if you have one incident every 5 years of a couple pounds of MOX burning up in the atmosphere, the radioactive hazard would be basically undetectable, there's just too much atmosphere

>>5736998
again, this pays for your electric bills AND the gas in your tank, since you're no longer paying for gasoline. factor that into the pays-for-itself value

>>5736959
oh, almost forgot. look into flywheel energy storage, either replacing or in addition to batteries. there's a company making a one ton flywheel in a vaccuum with magnetic bearings that can supposedly release a continuous 15kW for over 8 hours (through the night, max load), and has a 2% idle energy loss to friction or whatever. it blows batteries the fuck out of the water.
i think the company wants to have a commercial model on the market by late 2014 or something?

how to not pay power or water bills, or pay for gasoline ever again

1) buy about 15kw of solar panels off ebay. at the current price of 70 cents a peak watt including the grid tie, that's like $10,500. this will basically cut your power bill down to nothing (you still need the grid tie for baseload). and you'll also need a battery bank big enough to last you through the night. probably another $3k

2) get a parabolic solar water heater, both for water distillation (for purifying water) and also to heat A/C collant for your air conditioner/heater. using this you can capture rainwater and continuously recycle it with distillation and a small reservoir tank. The piping hot water could also potentially sterilize your waste water and break it down into compost. This can get somewhat complex though, what with filters that need to be cleaned. Also consider drilling a well.

3) buy an electric car. get a small trailer and a gasoline electric generator as well. Around town just use the batteries, and hook up the generator for long trips. charge your car off the solar panels when you're not driving

4) get a satellite or 4g internet connection. it's not cheap, but you have nothing else to really spend on aside from food, so fuck it

you could go even crazier and build your own greenhouse, but that's another hurdle and a half

tl;dr SOLAR ROCKS FOR OFF-GRID LIVING but is garbage for generating baseload.

>>5732885
i would like to interject by saying
>fuck yeah MTF
that is all

>>5729238
http://www.nydailynews.com/news/world/power-plant-stricken-tsunami-leaking-radioactive-water-article-1.1332275
yeah, sounds about right. the plant was quite old.
the lack of a cited source for anything in the article is a little weird though

>Even so, the farmer said that it is "impossible" to continue his work because of the radiation levels. “Our community will disappear. It's going to become like Chernobyl,” he said. “Children will never return."
unfortunately the japanese media has really bee running with all this. the area around the plant (more than about 5 miles away) is mostly fine. but there have been several radiation scares that never panned out. like a tapwater radiation hazard scare that ended up being literally nothing

>>5729251
i suspect they're going slowly and carefully with construction to avoid the NRC coming in and saying "wait no that's wrong tear it down". mixed with incompetence

>>5729237
heck, this group even flat out says it
http://www.ncwarn.org/2012/12/nuclear-construction-project-in-free-fall-duke-at-risk-too-news-release-from-nc-warn/
>Another lawsuit by watchdog groups including NC WARN is making its way through a federal appeals court, and is intended to stop Vogtle and other AP1000s until utilities incorporate lessons from the 2011 Fukushima disaster.
>it's not that we want the plant to be safer, it's just too expensive and we have NPPs so let's sue the bitch

>>5729224
ironically enough westinghouse sued the construction company for complying with safety standards
http://www.power-eng.com/articles/2012/11/third-lawsuit-filed-over-vogtle-nuclear-construction-costs.html
although to be fair those safety standards are tending to get a little silly

but there is this
http://atlanta.cbslocal.com/2012/02/17/environmental-groups-sue-to-stop-construction-of-nuclear-power-plants-at-vogtle/
which is basically just the post fukushima scare

>>5729212
>How much did the power plant cost go up because of court cases?
i am not certain about that, and have no sources. it seems quite difficult to find, possibly due to legal restrictions or the company just doesn't publish stuff like that

>>5729199
but isn't that sort of a self fulfilling prophecy?
>Nuclear waste is really dangerous! where are they trying to store it? "yuck-ah mountain?" where's that? OH MY GOD it's in the middle of nowhere! i must sue them to stop this madness it'll kill us all!
>cost of storage goes up because of court cases, and the eventual shut down of yucca mountain
>see! waste storage costs too much

really, you can store it in a giant concrete dry cask on the back lot of the power plant and it'll stay put until the sun explodes

>>5729192
but isn't that sort of a self fulfilling prophecy?
>NPPs cost too much! and are dangerous! i better sew that construction company for millions to keep it out of my town!
>cost of construction goes up because of court cases
>see! NPPs cost too much!

>>5729193
do you have any idea how sensitive the radiation detectors on their water coolant outlet tubes are? don't walk in there with a cigarette.
in addition, do you know how incredibly precise they need to be with the outlet water temperature? nature conservatories often pop up around NPPs because of how incredibly non-intrusive they are

>>5729196
i rather like high temp reactors, they seem to require more exotic types of materials though, more of a headache, also pressure issues. i'd prefer a high temp gas cooled once-through salt design m'self. don't gotta worry about it for a long ass time

>>5729175
i'm saying they're bashing subsidies of volatile markets, claiming that nuclear is volatile and renewables are solid, when it's basically the opposite

>>5729169
sounds about right, i'd like to see that correlated to number of court cases opened to sue the construction company
i'd also like to see dollars per MW averaged over the entire lifetime of the plant, since that seems to cover ONLY construction, which is ALWAYS much more expensive than operating costs for nuclear power plants....but they run for fucking 60 years generating revenue

>>5729155
financial risk (not health risk, which is probably what you're confusing it with), which renewables still have a lot of. see various green energy upstarts going under because they cannot compete and such. i just find the double standard hilarious