One has to wonder...
... if the shot director said "commence primary ignition" and the whole lab made a downward -sweeping tone as it came up to full power.
Mines the one with the UV absorbing weave.
The world's most powerful laser has fired a record-breaking pulse that exceeded even its own design goals. For 23 billionths of a second, the 192 ultraviolet lasers in the National Ignition Facility generated the equivalent of 411 trillion watts of peak power, which the NIF described as being 1,000 times more energy than the …
Whether half the lab followed it with:
"Hwonkk Hwonkk-Hwonkk -Hwonkk -Hwonkk!
Hwonkk Hwonkk-Hwonkk -Hwonkk -Hwonkk!
Spatial rift -- OPENING!
Hwonkk Hwonkk-Hwonkk -Hwonkk -Hwonkk!
Hwonkk Hwonkk-Hwonkk -Hwonkk -Hwonkk!
Spatial rift -- OPENING!
HWEE HWEEE HWEEE HWEEE HWEEE!
HWEE HWEEE HWEEE HWEEE HWEEE!
TEMPORAL destabilization -- IMMINENT!
TEMPORAL destabilization -- IMMINENT!
If it "exploded", it couldn't have been in contact long enough to glow yellow hot. It certainly wasn't my experience when I did something similar. When I was in high school my lab partner and I dropped a large screwdriver across the terminals of a 12v auto battery the teacher had sitting in the front (this was before class started) There was some sparking, and the screwdriver welded itself to the terminals. It probably got really hot - no way to know as while it wasn't glowing no one was brave enough to touch it other than the teacher trying to knock it off with a wooden ruler.
Fortunately we didn't get in any trouble, since the teacher was the kind who didn't mind these sorts of "experiments" as its the sort of thing he'd have been likely to do himself . He once burned all the hair off one of his arms as an 8 foot tall flame leapt out of a gas nozzle when he was messing about for a class demo in a way the maker of that gas nozzle would clearly not recommend.
The battery was sitting on the table like that for the whole class, and after the first few seconds of sparking didn't do anything further, such as melting or exploding.
> They use magnetic fields to hold it in place.
Er, isn't the major advantage of the laser-ignited fusion that you don't have to confine the plasma? You shoot the lasers at a fuel pellet to ignite a miniature fusion explosion, harvest the energy from the short-lived fireball, then inject the next pellet for the lasers to ignite. So the reactor operates in a pulsed fashion, like an internal combustion engine.
Obviously, they will need the expertise of Dr. Otto Octavius, who has excellent experience building tritium reactors in the hollowed-out shells of buildings. It's only a wee little piece of the sun, after all, no big whoop. Use friggin magnets and such.
A 10" gummy bear is 1000x bigger than a normal gummy bear.
I didn't look for values for Gummy Tongues, Gummy Brains, and Gummy Hearts...
I found that when querying "Texas is 1000 times bigger than..."
(They are in Raleigh, NC...)
Butt, I suspect that anyone eating a 10" Gummy Bear will prosume (produce and consume) all sorts of MJs trying to send that gelatin consumption back in time....
Its really not much.. the 23billionths of a second is such a short duration it makes all the comparison numbers massive the 411trillion watts for example is joules per whole second. Its still only 2MJ total, which has been said above is about a car battery.
The next trick is to get more than 2MJ energy out.... how are they doing on that front? have they ignited fuel yet?
(btw just like black holes mini suns need fuel the fuel pellets contain enough fuel for the mini sun to burn for a tiny fraction of a second, meaning it will self extinguish very rapidly, containment is not necessary.)
Their objective is to prove that they can generate more energy in a single laser-driven fusion event than they need to create this very fusion event. If you ignore the fact that they spent significant amounts of energy to build, maintain and operate the whole thing, you might call this 'break even'.
Ooh, and of course they have the plans in the drawer to build the next generation ignition facility, which might actually generate electrical power. But that is some 30 years in the future ... some things just never change.
All very clever from a techie point of view, but ultimately going in completely the wrong direction. Even if they reach their ultimate goal of harnessing fusion and generating terawatts (at a price too low to meter), it's a massively high risk strategy. Why do we need electricity/energy? Ultimately so that we can keep warm, lighten our darkness, cook our food and automate tasks. If we develop a society where we have to spend umpteen billion to build one fusion reactor (albeit one that will provide power for 100 million homes) we are done for. Because what happens when that reactor fails? Or becomes controlled by one person or corporation? And suddenly 100 million homes are cold and dark?
One of the biggest plus factors for many forms of renewable power generation is that they can be built and used and controlled locally. (Okay, same is true of coal, oil etc, but that's often dirty and dangerous) . There isn't a single point of failure that can affect thousands or millions of people. If I want to make a pot of soup I don't want to have to be dependent on 192 DEATH-RAYS under the control of some greedy/crazy government/corporation.
Small is beautiful folks.
Some things can be miniaturised - transistors, my earning power, etc.
Some things are subject to fundamental physical constraints which make them hard (maybe even impossible) to miniaturise.
It's been a long while since I looked in detail at NIF but I'd be very surprised if the technology could be miniaturised in any meaningful way.
In fact as has been pointed out, it's not even intended to supply power on a continuous basis (ie not pulsed) which in itself raises quite a few questions re adapting the technology for meaningful power generation.
Power from fusion is still twenty years away, same as it has been for decades.
K.I.S.S. is a good idea in general. All eggs in one basket is a bad idea in general. Not sure why so many downvotes for the K.I.S.S post, but I guess I'm next.
Thanks for that, I have indeed looked in reasonable detail at infernal and external combustion engines, both rotating and reciprocating, thank you. Thermodynamics was one of my favourite subjects when I took my physics degree. Solid state physics was another. I don't do physics any more, I are engineer.
Have YOU looked in any detail at how the fusion people are proposing to extract electricity from their pulsed fusion reactions?
Go on, give me a link or three, and someone with a clue will pull the physics and/or engineering to pieces within hours. Not *just* because it's pulsed, but the pulsing isn't exactly helpful.
Power from fusion is always twenty years away. There's a kind of poetry in that statement.
But, and it's a big but, we only need one working example to be able to replicate it.
Once we have one generator pushing out the watts, it can be used to power the next experiments, for free.
Overnight it will have more funding than the oil industry.
Not true about miniaturization. Scientists have noted that technology for much smaller lasers exists today, so the same facility could be rebuilt much smaller say ten years in the future, at which time advances the military is making in making high-powered compact lasers would allow it to be more compact ten years from then, etc.
Solar (PV or thermal)
It's not economically competitive yet against burning fossil fuel(*), but if those fuels were not available it could certainly take over the planet's electricity generation and maintain a technological civilisation.
(*) Had just about got there in Arizona, but then the gas industry worked out how to extract tight gas by fraccing, and now there's a natural gas glut in the USA.
Solar have a tendency to be quite unefficient at night and during winter.
Energy needs are at a peak during winter.
I won't even start to comment on the effects of desert sand dust on solar pannels or on mirrors.
However, solar is still a good way to reduce the energy needed for heating water in sunny areas.
Here we have the big problem. If you are going to supply a lot of power from wind, you have to average it over a large grid to minimize the amount of backup power needed. Thus, the more competent advocates of renewables concede the need for much investment in the U.S. grid. (I don't know anything about the U.K. grid, it might be a marvel).
"One of the biggest plus factors for many forms of renewable power generation is that they can be built and used and controlled locally."
Well, let's go back in time... back to the 1800s...
All the major factories have their own local power generators - steam engines mostly. All the needed power was built and used and controlled locally.
The trouble was that the maintenance was a chore, the generator was not used to full capacity most of the time and if anything break, ouch.
Those are most of the reason for the switch to the centrally produced/grid distributed network we've got now.
- Maintenance : you don't need 1000 times the people to maintain a generator 1000 times more powerful. (heck! it's a good point! it creates jobzzzz! who care if the leecy bills goes up thru the roof due to the extra costs)
- Capacity : It's still a major issue, but it is far smoother than before.
- Breakdown : if one station fails, other stations can usually cope with it. Japan is still mostly functionnal even with the loss of one of the most powerful nuke station in the world*
- Reliability : The new** renewables are mostly those damned unreliable windmills that may produce 25MW one day and 0 the next...
If you've got another way for solving the last 3 issues than keeping a grid system, just tell me, I'm all ears.
And if you're stuck with a grid system, good luck to manage it if it's not centrally controlled...
Controlling the production is useless if someone else controls the distribution.
*I know, Fuckushima was planned for retirement, and the backup was already in place...
** Hydroelectric is not a new renewable. It have a lot of major advantages, like cheapness, mature technology, capacity and localized environnemental damages (Turning valleys in huge lakes *is* environmental damage...). And guess what? Power companies knows it and already invested in it since the beggining. In a lot of countries, there is not much room for further exploitation. Geothermal is another reliable renewable, but you have to live on a freaking volcano for it to be economically viable.
the local library had several science fiction anthonlogies and in one story, if i remember correctly it was called Bilbo's Star, people could make their own star rather like building a airfix model, only Bilbo's star was not quite right, more of a rugby ball shape and the more he "fed" his star to try and make it look the right shape the worse it got until one day it collapsed on itself and started to devour everything. Articles like this always remind me of that story. No real point, just thought i would share.
This is fascnating but one point with fusion reactors that never seems to be addressed is how to get the energy into electricity generation. A laser chamber seems to be even worse at this than the magnetic confinement systems we've played with since the fifties.
The reaction is inside what amounts to a huge vacuum tube so it won't convect out. You could let the radiance make the enclosure hot enough to allow decent thermodynamic efficiency but at the same time you have to keep the laser objectives or superconducting coils cool and stable.
Some sort of MHD generation might be a runner, but the fusion reactions that get discussed yield high proportions -- like 80% -- of the energy in fast neutrons, and neutrons don't play the magnetic game.
The only really practical means I can see is to line the chamber with depleted uranium and let the neutrons breed plutonium and other transuranics to fuel fission reactors. But that seems a bit of a palaver compared with running a fast breeder fission reactor directly. I'm flummoxed.
Actually this is solved at the same time as the tritium breeding problem. The fusion reaction currently envisaged is deutrium-tritium fusion. Tritium is not a naturally occurring element so it has to be bred by neutron bombardment of lithium. This reaction has a reasonably high cross section so it can absorb a fair number of neutrons and produces tritium and helium which then stop fairly rapidly in solid materials depositing all the original neutron energy. The net result is that the lithium blanket heats as it generates the needed tritium, and the heat can be recovered in fairly conventional ways.
Designing these blanket systems is a fairly big engineering problem, but it's almost certainly solvable once we've got a self-sustaining fusion reaction to go in the middle.
NIF is funded largely by the military. It's primary purpose is to be able to examine the physics of fusion reactions without letting off H-bombs. The whole "fusion energy" angle is merely great PR.
To make this into a commercial fusion generator, you have to scale things up somewhat.
Currently NIF fires a few shots per day. To make a commercial reactor, you'd have to fire about 10 shots per second.
So instead of carefully positioning the fuel target in the centre of the laser array with micrometre precision, you'd essentially need a machine gun. A cryogenically cooled machine gun that never misfires and shoots with micrometre precision.
Oh, and the ammunition. The fact that each round is composed of a fuel pellet contained in a beryllium sphere surrounded by a cylinder of gold-plated uranium is not what makes the fuel expensive. What makes the fuel expensive is that it contains tritium, one of the rarest substances on Earth. The USA has only ever made 225kg of this element, and only 65kg of it is left - most of that loss just from natural decay. Even though each pellet only has a few mg of fuel, at 10 shots a second, you'd burn through that tritium reserve in less than a year, for just one reactor.
And how to extract energy? Well, you have to take the heat and generate electricity... so you have to put a large heat exchanger in the reactor. And somehow not obstruct the laser array that shoots the pellets when you do so.
Oh, and the laser array... currently about 1% efficient. So you'd have to either improve that greatly, or generate more than 200 times the energy you put in (accounting for efficiency of steam turbines). And ramping things up to make the laser fire 10 times a second seems difficult given they currently only fire a few shots a day.
Laser-initiated inertial confinement fusion does not seem practical.
This is, of course, basically exciting news and while those who are pointing out the practical issues associated with extracting energy from fusion have a point, I'm inclined to wave my hand and say 'Pfft! Engineering my friend.'
Of course, that comment only holds true once we've got net power gain from a fusion process.
*excited about visit to Culham on 11th April*
About 2006 Brian Cox had a tv series touring the world looking at fusion power trial work.
He showed this, it is massive in what looked like an aircraft hanger.
At the end of the series he was asked what he thought the most promising and replied this one. So he is not just a pretty face.
"which the NIF described as being 1,000 times more energy than the entire US uses "at any instant in time"."
I hope they didn't. It's 1000 times more than the *power* drawn by the US over any normal timescale, but the failure to distinguish between energy and energy-per-unit-time is a bit sad, given that the point of the sentence was to play a game around that very idea.
You beat me to it. Thank you.
If you talk about "energy at any instant in time" you are talking nonsense, as energy is power * time - let time go to zero (an instant) and energy by definition goes to zero too.
And I'd hope anybody working on fusion would know the difference - and I'm sure they did. But the meatbag of a distorter^Wreporter didn't.
there is a design for an interplanetary/interstellar drive called a Daedelus drive - see :
Lucifer's Hammer, Niven & Pournelle also see : http://en.wikipedia.org/wiki/Nuclear_pulse_propulsion
But in both of these instances, the propulsion was fission - however, hydrogen is plentiful in the universe in general, and a pulsed FUSION drive might be a workable concept, at our current level of technology. Sort of a mix between a Bussard Ramjet (en.wikipedia.org/wiki/Bussard_ramjet) and Daedelus drive.
btw - just to complete the sci-fi references :)
Tau Zero, Pol Anderson - is an interesting story about the use of a Bussard ramjet
icon for obvious reasons :)
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