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A Star in a Bottle

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Re: A Star in a Bottle

#141

Post by prewett »

sbierwagen wrote: post #90
jackgavigan wrote: post #9

As a child, I read Friday by Robert A Heinlein, which portrayed a future in which energy needs are addressed by energy storage devices called "Shipstones", which are described as a way to pack more kilowatt-hours into a smaller space and a smaller mass than any other engineer had ever dreamed of. To call it an "improved storage battery" (as some early accounts did) is like calling an H-bomb an "improved firecracker."…

Also, what happens if the mechanisms that contain the "Star in a Bottle" fail? Will the French Alps suddenly and catastrophically acquire a new valley? This is a reasonable concern, but your intuitions on the physical processes involved are off by a couple orders of magnitude. From a previous comment on another fusion story, two years ago: http://news.ycombinator.com/item?id=2839722 Fusion reactors are fundamentally…

That addresses the concern about the fusion reaction. But when the plasma melts a hole in a building-sized vacuum chamber and air suddenly rushes in, I expect that you'll get a big implosion, which will ricochet off itself and become an explosion, like if you punched a hole in a CRT with a nail. The article talks about a solenoid that exerts more force than the Space Shuttle does to lift itself to orbit. When the vacuum chamber deforms the solenoid, that energy is going to go somewhere. Plus, they mention gigajoules of electricity going through superconducting wires. I expect that the vacuum chamber implosion would destroy them before they heated up and no longer became superconducting. So instead of gigajoules going through essentially giant resistors and heating up something fierce, that energy will do something else, not sure what.

I don't think this will destroy a mountain, but I would expect the reactor and building to be catastrophically destroyed by the vacuum chamber implosion, along with some, shall we say, interesting, but certainly powerful, effects from the solenoid and other magnets.

Re: A Star in a Bottle

#142

Post by prewett »

drjesusphd wrote: post #135
Flammy wrote: post #34

Obviously the tech is really awesome, but I was curious how the projected power level compares (500 megawatts) Comparison to existing powerplants: http://www.wolframalpha.com/input/?i=500+megawatts TL;DR: We already have significantly bigger plants. ('average' coal and nuclear plant produces about twice as much power)

But there's only a few hundred years' worth of uranium and coal remaining (and we better not be burning the latter for that long for greenhouse reasons). There is millions' of years worth of fusion fuel on Earth. The fact that it's "only" half a coal plant is hardly a criticism.

Well, $20 billion and counting for half a coal plant is a bit of a problem... And actually, it's not half a coal plant, because the half coal plant is net + 500 MW, and since ITER isn't supposed to reach the ignition point, the output is 500 MW, but the input is > 500 MW.

If fusion requires wonder-of-the-world kind of technology to not even break even, it makes me somewhat pessimistic. (However, I still say, more power to them, fund them, let's see where this goes)

Re: A Star in a Bottle

#143

Post by bobsil1 »

brc wrote: post #137
mathattack wrote: post #67

Earlier quoted context omitted.

Call me naive, but I think it was Junior surrounding himself with folks who wanted him to finish the job that Pops started. I think they (like most who start wars) dramatically underestimating the costs and complexity. I'm less inclined to believe that it has to do with gassing their own people (why start caring now?) or going to the Euro. But I do agree with the above points that we spend an awful lot of time fighti…

I would say brinkmanship and groupthink are a much more likely explanation than theories about defense spending or oil production or currencies, which fall flat on analysis. Not to say that people didn't make hay with government contracts, but there are easier ways to swindle public cash than to get high-placed politicians to start wars. It also leaves out a very significant factor : vote winning. Patriotism wins ele…

>there are easier ways

If you're a military contractor, a military buildup or war is optimal.

Re: A Star in a Bottle

#144

Post by bobsil1 »

nickstinemates wrote: post #81
sitkack wrote: post #79

Earlier quoted context omitted.

Correct, but that is a failure of the carriers not supporting their customers. Cellular carriers should be supporting VOIP over data (3g,4g) and internet wifi. But since they are rent seeking, they won't disrupt their voice and sms traffic, enabling plays like WhatsApp.

No debates there; it will be interesting to see how phone carriers fight being 'dumb pipes', which I believe we all want to see as inevitable.

PSTN and TV are dead, they just don't know it yet.

Re: A Star in a Bottle

#145

Post by benjamta »

sliverstorm wrote: post #114
benjamta wrote: post #2

My father worked on the ITER project for many years. This article goes some way to express the shear scale of this project, it's absolutely vast. When I was a lot younger I was taken on a tour of JET ( http://www.efda.org/jet/ ) and was overawed with the size of it. ITER is an order of magnitude bigger. The machine that follows ITER is where things get really interesting. Called DEMO, it's still in the planning phase…

Hate to nitpick, but it's sheer scale Shear is a verb (or noun); I shear the sheep Sheer is an adjective; I was awestruck by the sheer cliffs

quite right - thanks for pointing that out :)

Re: A Star in a Bottle

#147

Post by leoedin »

lloeki wrote: post #85
leoedin wrote: post #45

Earlier quoted context omitted.

The article's full of fairly silly elaborate descriptions. My favourite so far (3 pages in): > Some in the field believe that a working machine would be a monument to human achievement surpassing the pyramids of Giza. Which suggests that the pyramids of Giza are a monument of human achievement that hasn't yet been surpassed. You only need to take a look at almost any 20th century bridge, skyscraper or even ship to kn…

> the pyramids of Giza are a monument of human achievement that hasn't yet been surpassed. > [...] the last few centuries have completely and utterly surpassed that In terms of what they were built for, that is travel through time mostly unharmed for several thousands of years, a literal vessel of eternity, this claim is undebatably false. Few things we have built in the last two centuries will survive more than a de…

Many, many things last more than a decade. A stone house (of which there are many abandoned in the UK) will stand visibly for centuries.

There are many differences between bunkers and the pyramids. The biggest one is that bunkers were designed to be as low profile as possible. They are nowhere near the scale of the pyramids. Probably the next most important difference is the location. The pyramids were built in a desert environment which is hostile to the biggest enemy of manmade buildings - vegetation.

I'm not arguing that the pyramids aren't an incredible feat, or a monument to the achievement of an otherwise very low-technology early society. What I'm arguing against is the idea that the building of a fusion reactor would somehow be the first human development which would surpass the pyramids of giza as a monument of human achievement. The fact we have spacecraft in distant orbits which will remain exactly as they are for centuries or millenia is surely a much greater monument (albeit one which is hard to find). Our major cities (which are so entrenched that even if they were abandoned today would exist in some form for centuries, and certainly be easily identified for millenia) are vast monuments of human achievement. Can you really argue that the entirety of London is less of a monument of human achievement than the pyramids of giza?

Re: A Star in a Bottle

#148

Post by pandler »

I hate for my only comment on this fascinating piece to be largely irrelevant, but has anyone else noticed that the publication date is March 3, 2014? It's only the 25th of February.

Re: A Star in a Bottle

#149

Post by spikels »

Zikes wrote: post #58
slacka wrote: post #51

It's crazy that the US blew over 4 Trillion and countless lives for oil in Iraq. Yet, we spend practically nothing on technology that could offer clean, safe, energy independence. I'm happy to see any money going into fusion research, but it does seem that Focus Fusion has a much better chance of delivering in the near term. If you're unfamiliar with the technology, check out the Google tech talk below. http://www.yo…

We didn't go to Iraq for oil, we went there so that more of our own money could be funneled from government coffers into politicians' bank accounts by way of defense contracts.

"Never ascribe to malice that which is adequately explained by incompetence." -Napoleon

Re: A Star in a Bottle

#150

Post by dredmorbius »

jackgavigan wrote: post #146
bicknergseng wrote: post #127

Earlier quoted context omitted.

1735 kilograms (Ferrari California curb weight) * (the speed of light^2) = 1.55934024 × 1020 joules

How many Hiroshimas is that?

Well, that turns out to be a unit of energy which GNU unit (my favorite shell utility) doesn't have, nor does it have kilotons (or tons) of TNT).

However I've found a calculator that does do kilotons of TNT:

http://lectureonline.cl.msu.edu/~mmp/conversions/conv_energy...

So one Ferrari is 37.13 * 10^6 kilotons. Hiroshima was 15 kt, so one Ferrari contains the energy released in 2,475,333.3 Hiroshima atomic bombs.

And for reference, 1 kilotonTNT is:

4.200e+12 joule

1.003e+12 calorie

1.003e+9 kilocalorie

At 3600 kcal/lb fat, one kilotonTNT is equivalent to 278,611.11 lb of fat. Which is to say, if everyone (313 million people) in the US lost 1/5 of an ounce each, the energy released would be equivalent to one Hiroshima bomb.

3.978e+9 BTU

1,167 MWh, or 1.2 GWh. Roughly the energy a large generating plant produces in an hour. Which is to say that the time over which you release energy matters.

And you've also inspired me to figure out how to add my own units definitions, so now I have kttnt:

686 barrels of oil, almost exactly 100 tons of oil, 1.16 GWh, 143 toncoal, 154 tons of charcoal, or about 51 grams of pure uranium.

And checking: 100 tons / 51 grams is 1,778,793, which is to say, atomic energy has roughly 1 million times the energy storage density of our best chemical energy sources.

You'll note that 100 tons of oil is a lot less than a kiloton (1000 tons) of TNT. Turns out that what makes TNT so special isn't its energy content but the rate of release of that energy. Oil (or aviation fuel as the occupants of 120 Cortlandt St., NYC, discovered a few years back) has about 10 times the energy content of explosives, it just delivers it over a longer period of time.

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