Slashdot is powered by your submissions, so send in your scoop

 



Forgot your password?
typodupeerror
×
Power Science

Fusion Reactor Breaks Even 429

mysqlbytes writes "The BBC is reporting the National Ignition Facility (NIF), based at Livermore in California, has succeeded in breaking even — 'During an experiment in late September, the amount of energy released through the fusion reaction exceeded the amount of energy being absorbed by the fuel — the first time this had been achieved at any fusion facility in the world.'"
This discussion has been archived. No new comments can be posted.

Fusion Reactor Breaks Even

Comments Filter:
  • by ne0n ( 884282 ) on Monday October 07, 2013 @07:13PM (#45065093) Homepage
    Cool. Let it run the US gov't.
    • bbc? (Score:5, Interesting)

      by noh8rz10 ( 2716597 ) on Monday October 07, 2013 @07:15PM (#45065113)

      why is the bbc first to report on this? It happens in CA, and we get scooped? wtf??

      • Re:bbc? (Score:5, Funny)

        by Obfuscant ( 592200 ) on Monday October 07, 2013 @07:30PM (#45065243)

        why is the bbc first to report on this? It happens in CA, and we get scooped? wtf??

        It's 5 to 8 hours later in England than it is here. They've had a few more hours to report on it than we have.

        But what's this "break even"? If it produced more than it consumed, it's not "break even".

        • Re:bbc? (Score:5, Informative)

          by ewibble ( 1655195 ) on Monday October 07, 2013 @07:49PM (#45065399)

          Not quite, the whole system it actually consumed more than it produced. The power outputted by the lasers was less than was produced. There are inefficiencies in the lasers so net power is negative.

          • Re:bbc? (Score:5, Interesting)

            by TheInternetGuy ( 2006682 ) on Monday October 07, 2013 @08:02PM (#45065501)

            Not quite, the whole system it actually consumed more than it produced. The power outputted by the lasers was less than was produced. There are inefficiencies in the lasers so net power is negative.

            Yes and in an future power producing environment, the thermal power output needs to be converted to electricity. Typical thermal power systems does this with an efficiency of about 33-48%, so there is still a way to go. Still they are making fast progress compared to ITER, which have had a good head start.

            • Re:bbc? (Score:5, Funny)

              by Cryacin ( 657549 ) on Monday October 07, 2013 @09:13PM (#45065943)
              So in other words, "almost breaking even!". Just like everyone at the casino.
              • Re:bbc? (Score:5, Informative)

                by VortexCortex ( 1117377 ) <VortexCortex AT ... trograde DOT com> on Monday October 07, 2013 @10:02PM (#45066219)

                Yes, except that a jackpot can be duplicated as many times as you want without getting your knees broke.

              • Re:bbc? (Score:4, Interesting)

                by Maury Markowitz ( 452832 ) on Tuesday October 08, 2013 @06:14AM (#45068275) Homepage

                "So in other words, "almost breaking even!"."

                Not even close.

                The input to the lasers is 422 MJ. The output is 1.8 MJ. So if the input/output was ~1.8 MJ, then the system as a whole is operating at about 0.4% of break even.

                This is not an "important step" towards anything. The NIF system cannot be used as the basis for a power plant, something everyone, including the NIF, is very much aware of. It is an experimental system for studying matter at high densities, and not even very good at that.

                • Re:bbc? (Score:4, Insightful)

                  by hyperquantization ( 804651 ) on Tuesday October 08, 2013 @09:30AM (#45069827)

                  This is not an "important step" towards anything. The NIF system cannot be used as the basis for a power plant, something everyone, including the NIF, is very much aware of. It is an experimental system for studying matter at high densities, and not even very good at that.

                  It is incredibly important. At the very least, it's proof that the problems associated with fusion power are solvable. But most importantly, this news will funnel more cash towards further fusion research, further accelerating progress towards real actual power plants.

                • by vux984 ( 928602 )

                  This is not an "important step" towards anything. The NIF system cannot be used as the basis for a power plant, something everyone, including the NIF, is very much aware of. It is an experimental system for studying matter at high densities, and not even very good at that.

                  The input absorbed by the fuel is less than the output at the fuel. That is a very important step, showing that we can actually get more energy out than we are putting in.

                  Yes, the net energy of the entire system is still very negative, and

            • Re:bbc? (Score:5, Interesting)

              by amaurea ( 2900163 ) on Tuesday October 08, 2013 @04:08AM (#45067789) Homepage

              What do you mean by ITER having a good head start? ITER is still a giant construction site! Here's what ITER currently looks like [google.com]. Yes, it's that hole in the ground.

              It would be interesting to read more details of NIL's achievement, though. For example whether this was breakeven using deuterium-tritium fuel, or whether they looked at their performance with less hazardous deuterium-deuterium fuel, and then extrapolated to performance with D-T. If the latter, then that has already been achieved by the japanese JT-60 tokamak in 1998 [wikipedia.org]. ITER is expected to reach 10 times breakeven with real D-T fuel, and be significantly net power positive [wikipedia.org].

              The problem with inertial confinment using laser heating, as is used by NIL, is that not only is energy transfer from the lasers to the plasma inefficient, but much more importantly, generating the laser beams in the first place is extremely inefficient, resulting in a wikipedia article correctly. This makes inertial confinement fusion unlikely for energy production according to most people I've spoken to. It is useful for researching the behavior of high-energy plasmas though, which is useful for designing nuclear weapons.

              • What do you mean by ITER having a good head start? ITER is still a giant construction site! Here's what ITER currently looks like [google.com]. Yes, it's that hole in the ground.

                I meant that ITER the project was initiated in 1988, thus giving them a good head start. I didn't say that they were still ahead.

                • Re:bbc? (Score:4, Informative)

                  by amaurea ( 2900163 ) on Tuesday October 08, 2013 @04:38AM (#45067905) Homepage

                  When was the NIF project initiated? I found a "funding confirmation" in 1993, but not when the project itself was started. But if it was less than 5 years earlier, then ITER had a head start bureaucracy-wise.

                  NIF construction itself started in 1997, while ITER's started in 2008. So if you ignore the time spent on bureaucracy, NIF has had an 11 year head start. But I think the most interesting comparison is not planning time or construction time, but results/time after the facility opens. That will have to wait 7 more years, though.

              • Re:bbc? (Score:5, Funny)

                by Provocateur ( 133110 ) <shedied@gmai[ ]om ['l.c' in gap]> on Tuesday October 08, 2013 @08:22AM (#45069091) Homepage

                Yes, it's that hole in the ground.

                Actually that's their after-their-first-lab-test photo.

            • Re:bbc? (Score:4, Informative)

              by johanw ( 1001493 ) on Tuesday October 08, 2013 @04:56AM (#45067989)

              That's why we speak of "physical break-even", which was, according to some definitions, reached here, and "technical break-even", which takes into account the efficiency of the whole system and compares power in with usable electricity out.

        • Re:bbc? (Score:5, Informative)

          by Anaerin ( 905998 ) on Monday October 07, 2013 @07:54PM (#45065441)

          Time flows the same in England as it does in the US, and they get the information at the same instant as the US (Barring marginal transmission delays). If it was a case of hours and timezones, I might agree with you somewhat, but as the freakin' summary quotes: "During an experiment in late September," (Emphasis mine).

          Even assuming that means September 30th, that's 7 days the US press has had to sit on this. At that point, the fact that the UK is 5-7 hours ahead doesn't make an iota of difference (Well, technically I guess it makes 4.1666% of difference, but that's hardly the point).

          Oh, and why is <sup> getting stripped out of /. HTML?

          • Results of such experiments sometimes take days to be known and verified to the point of publication. The news reported in early October may well be as early as possible. Who knows why the US press did not get it out first?
            • Re:bbc? (Score:5, Insightful)

              by The Grim Reefer ( 1162755 ) on Monday October 07, 2013 @09:26PM (#45066021)

              Who knows why the US press did not get it out first?

              Because if it's not about what some republican or democrat said about the other regarding the budget, ACA, or debt limit nobody is interested right now. Getting one step closer to fusion power just doesn't scare the crap out of anyone, or piss them off like the other issues right now. If you can find a janitor that once worked at the facility and is claiming that there's an out of control black hole that's going to destroy the sun, turn mankind into vampires and vaporize the spotted owl, then we'll hear about it.

            • Re:bbc? (Score:5, Funny)

              by Beeftopia ( 1846720 ) on Monday October 07, 2013 @11:22PM (#45066559)

              Who knows why the US press did not get it out first?

              Three words: "Miley Cyrus twerked."

              Google Trends search term popularity. [google.com]

              Achieving fusion break-even just when a skinny white girl learns to twerk is just wrong place, wrong time, baby.

              • Science needs more strippers.

                • I would totally support a strip-off for science.

                  Actually, isn't this the sort of thing that Burlesque covers? Don't they do kooky themed things every now and then? The Star Wars burlesque made some waves a little while ago. Where's my science themed show? A burlesque version of that skit showing how elements react [youtube.com] would be hilarious. Among other things.

                  I'm sure with only some minor instructions, the dancers would be able to work alongside Jacob's ladders and liquid nitrogen.

          • Re:bbc? (Score:5, Informative)

            by Immerman ( 2627577 ) on Monday October 07, 2013 @08:37PM (#45065705)

            The *experiment* was in late September. Researchers tend to be rather cautious about announcing significant milestones, especially in high-profile areas such as this, taking time to double check their numbers and the like beforehand. I can easily see the process taking a few days or weeks before they're ready to make a statement.

            As for getting the information the same instant the world over - how exactly do you see that happening? The scientists send a press release to (presumably) a small number of news organizations (the BBC probably being one of them). All other organizations hear about it second-hand, likely meaning at least a fair portion of a day, possibly several days, before it's published, and another delay before anyone else can publish anything more than a blatant plagarization. Repeat that a few times before it hits some other news stream that you watch and...

            Sure the info probably went up on the researchers website about the same time as the press release, and that is available to everyone everywhere, but I would suspect that very few people routinely check the websites of random researchers on a daily basis - after all it's not something important like the latest celebrity scandal[/sarcasm], it won't make any difference to most people if they don't hear about it for a few days.

        • Re:bbc? (Score:5, Funny)

          by Anonymous Coward on Monday October 07, 2013 @08:01PM (#45065495)

          Here in Australia we got today's news about the NIF reactor yesterday.

      • Re:bbc? (Score:5, Insightful)

        by Enter the Shoggoth ( 1362079 ) on Monday October 07, 2013 @07:30PM (#45065247)

        why is the bbc first to report on this? It happens in CA, and we get scooped? wtf??

        Given that a lot of formerly serious news agencies have resorted to the tabloid approach for everything it shouldn't be overly surprising that an institution that isn't beholden to market forces and has a long history of effective (and independant) investigative journalism would be first.

        In other words perhaps having a "stiff upper lip" isn't such a bad thing after all.

      • Re:bbc? (Score:5, Insightful)

        by hawguy ( 1600213 ) on Monday October 07, 2013 @07:34PM (#45065285)

        why is the bbc first to report on this? It happens in CA, and we get scooped? wtf??

        Because Americans don't care about science and if you told the typical American that we achieved nuclear Fusion, they'd say "That's the same thing that killed all those people in Fukishima, we don't need that sh*t here!"

      • Re:bbc? (Score:4, Interesting)

        by Epell ( 1866960 ) on Monday October 07, 2013 @07:51PM (#45065423)

        US news agencies are busy covering government shutdown.

        • by Grave ( 8234 )

          I initially read that as "celebrating" instead of "covering". I think my mis-read might be just as accurate, sadly.

      • by smash ( 1351 )
        Because your media is more interested in reporting on crap like bennifer.
        • bahaha bennifer is like 15 years ago. if anything today it's kimye, but that's even a year or two old now. but i think england is the king for trashy tabloids. page 6, anybody?

      • Re:bbc? (Score:4, Insightful)

        by bmo ( 77928 ) on Monday October 07, 2013 @09:02PM (#45065875)

        why is the bbc first to report on this?

        Because of the Fox effect.

        US news outlets have become so dumbed-down that in order to get what used to be regular news, one must pay attention to foreign broadcasters and read foreign print media (on the web, natch). I have NBC World News (the most ironic title ever) DVRed, and I FF through most of it. The rest of the Big Three, CBS and ABC, are like NBC - fluff. CNN Headline News doesn't even exist anymore. BBC, CBC, SRI (which went satellite only in 2004 and web as swissinfo.ch), DW, Al Jazeera, etc. All more reliable and informative than anything here. I skim the local news and anything national is covered far better by foreign press. And then there is just going to the wire services directly.

        Fox "news" is just horrid. The lowest of all of them, catering to the lowest possible denominator - the people most easily propagandized. Since doing this sells a lot better than anything "intellectual", the other networks followed right on down the road to mediocrity. Thus the Fox effect.

        As for print, nobody in his right mind reads Time, Newsweek, or US Snooze. Ever since the WSJ became a Murdoch property, that is also suspect, especially in the editorial department.

        One reads the Pink Paper and The Economist. Even The Guardian is better.

        None are US based.

        --
        BMO - The Scousers never buy The Sun.

    • .... you seriously don't see the practical real world uses for a fusion reactor that produces energy above parity?

      Turn in your geek card, please. :)

  • Mr Fusion (Score:5, Funny)

    by jimbouse ( 2425428 ) on Monday October 07, 2013 @07:14PM (#45065099)
    Mr. Fusion here we come!
  • by Anonymous Coward

    And about time too. I imagine there is still a great deal more work to be done before this is of any real use, but still wow. Just wow.

    • by NoNonAlphaCharsHere ( 2201864 ) on Monday October 07, 2013 @07:36PM (#45065303)

      ...the amount of energy released through the fusion reaction exceeded the amount of energy being absorbed by the fuel...

      "Energy released" is COMPLETELY DIFFERENT than "energy generated". They've simply reached the point where causing a fusion reaction doesn't require more input energy than the reaction itself releases - HARNESSING the released energy (a large chunk of which is energetic neutrons, i.e. not recoverable) is another matter entirely.

      • by WalksOnDirt ( 704461 ) on Monday October 07, 2013 @08:18PM (#45065607)

        ...released energy (a large chunk of which is energetic neutrons, i.e. not recoverable)...

        The energy in neutrons is not unrecoverable. You would probably need to use a heat engine to get the energy out, but at high temperatures that could be efficient.

        The break even point is somewhat arbitrary, as any neutrons out will give you some heat. All you have to do is harness it. In practice, though, about 10X break even is thought to be necessary. To be economic you would need much more, especially since fission is so easy. Most fusion reactions will also create waste, and any reaction that creates copious neutrons will be a proliferation risk. Aneutronic fusion is very hard, and the NRC would probably crush anything else.

        It's a nice technical achievement, but I can't see us using it to produce electricity.

        • by Roger W Moore ( 538166 ) on Monday October 07, 2013 @08:59PM (#45065855) Journal

          The energy in neutrons is not unrecoverable.

          Not only is it potentially recoverable but there is a company here in Canada [generalfusion.com] looking at building a fusion reactor which can recover it. The reactor design is rather radical and by no means proven but having met the guy behind the company if it is at all possible he'll be the one to make it work!

          • Soooooo... There's a guy running a company looking at getting other people to give him money to build a fusion reactor which can... do whatever sounds like it'll make investor's panties wet.

            I dunno man, fusion power has had a whole hell of a lot of snake oil salesmen. Your post even raises some red flags because "you've met the guy". Seriously, unless you're a high-energy physicist and know your shit about fusion, that's a net negative data-point for this project. The more charismatic he is, ie, his ability

      • by wmac1 ( 2478314 )

        Besides, it does not mean they can sustain the reaction for a long time.

        I guess the reactions are still too short to be useful for energy production.

  • Comment removed (Score:5, Interesting)

    by account_deleted ( 4530225 ) on Monday October 07, 2013 @07:21PM (#45065173)
    Comment removed based on user account deletion
    • by mythosaz ( 572040 ) on Monday October 07, 2013 @07:23PM (#45065191)

      Weapons research always trickles down into practical applications.

      • Weapons research always trickles down into practical applications.

        Hard to believe anyone still falls for this nonsense - perhaps we should apply it to defense. Oh wait we already have... worked out well didn't it?

      • by quenda ( 644621 )

        Weapons research always trickles down into practical applications.

        But its not very efficient. It would be nice to have more than a trickle to show for the billions spent.
        Or at least some weapons useful against modern threats.

      • by mcrbids ( 148650 )

        Why is this modded funny?

        Digital cameras were strongly funded by military budgets. As was GPS, Vulcanized rubber (tires), jet engines, the Internet, and too many other things to name.

        I mean, perhaps not *always* but the ROI (to the civilian economy) for military innovation funding is actually surprisingly good.

      • You're modded as funny, but I'm betting the state of nuclear science would be nowhere near the state it is now if not for the Manhattan Project.

    • by Anonymous Coward on Monday October 07, 2013 @07:36PM (#45065301)

      Ah, my friend, you need the full quote:

      In 2009, NIF officials announced an aim to demonstrate nuclear fusion producing net energy by 30 September 2012. But unexpected technical problems ensured the deadline came and went; the fusion output was less than had originally been predicted by mathematical models.

      Soon after, the $3.5bn facility shifted focus, cutting the amount of time spent on fusion versus nuclear weapons research - which was part of the lab's original mission.

      However, the latest experiments agree well with predictions of energy output, which will provide a welcome boost to ignition research at NIF, as well as encouragement to advocates of fusion energy in general.

      Looks like the good of mankind may prevail, after all.

    • Actually that quote is taken out of context. FTFA: "In 2009, NIF officials announced an aim to demonstrate nuclear fusion producing net energy by 30 September 2012. But unexpected technical problems ensured the deadline came and went; the fusion output was less than had originally been predicted by mathematical models. Soon after, the $3.5bn facility shifted focus, cutting the amount of time spent on fusion versus nuclear weapons research - which was part of the lab's original mission." It's stating that
    • I wonder how many wars practical nuclear fusion would avert. I would wager that it would be more than the result of refining a nuclear deterrent.

      Still, these are the sort of breakthroughs I love hearing about. Good work, science.

    • Makes you wonder where we'd be now if we stopped pissing about on weapons research.

      We would have achieved the age of

      LIGHT

      without

      HEAT ... heat .. heat... (heat)

      And we would be so much more efficient at blinding our enemies before capping them.

      • Makes you wonder where we'd be now if we stopped pissing about on weapons research.

        We would have achieved the age of

        LIGHT

        without

        HEAT ... heat .. heat... (heat)

        And we would be so much more efficient at blinding our enemies before capping them.

        So does this mean we will soon have to deal with the following?

        1: Little green men about 4 foot 1, maybe they want to have some fun.
        2: Little green men about 4 foot 2, maybe they want to mate with you.
        3: Little green men about 4 foot 3, maybe they want to be set free.
        4: Little green men about four foot, maybe they want to kick some butt!!!

  • by Anonymous Coward on Monday October 07, 2013 @07:23PM (#45065193)

    Seems to have just a little more information than the source material :)

    https://lasers.llnl.gov/newsroom/project_status/index.php

    • From your link:

      >The shot resulted in the highest DT neutron yield obtained to date, estimated at nearly 3 × 1015 (three quadrillion), or almost 8,000 joules of fusion energy

      And then:

      >All 192 NIF beams delivered 1.7 megajoules (MJ) to the hohlraum

      That doesn't look like break even...

      • You are quoting figures from the August experimental results. I'm guessing the latest experiment that the BBC is reporting on is better than that.

        I'd also like to see some actual figures though.
    • Comment removed (Score:4, Informative)

      by account_deleted ( 4530225 ) on Monday October 07, 2013 @07:45PM (#45065373)
      Comment removed based on user account deletion
  • by dlingman ( 1757250 ) on Monday October 07, 2013 @07:30PM (#45065233)

    A few points - Still more energy needed than produced - because lasers aren't 100%. They exceeded the amount of light energy going in, but not the power level fed into the laser. Second, how much of the released energy was in a form that could be fed back in to make the next thingy go moob? Not seeing anything on that here...

    Overall though, it's a step in the right direction. Go guys go!

  • by cachimaster ( 127194 ) on Monday October 07, 2013 @07:30PM (#45065237)

    Fusion achieved. Sometimes we are awesome creatures, congrats to all involved.
    And not a minute too soon.

  • Helium? (Score:4, Interesting)

    by irving47 ( 73147 ) on Monday October 07, 2013 @07:31PM (#45065257) Homepage

    I don't know a lot of about fusion, but I've read Helium is a byproduct of fusion reactions. Once these things start getting run more and more, will we be able to harvest the helium generated to stave off the coming shortages?

    • Re:Helium? (Score:5, Funny)

      by ColdWetDog ( 752185 ) on Monday October 07, 2013 @07:42PM (#45065341) Homepage

      Yep, all you need is a 5 billion dollar fusion reactor to make a couple of bucks of helium.

    • Re:Helium? (Score:5, Informative)

      by niftydude ( 1745144 ) on Monday October 07, 2013 @07:46PM (#45065381)
      Helium is a byproduct - but the amount generated is tiny - the pellet for each fusion reaction only contains a few milligrams of hydrogen fuel, and so even less helium is generated.
    • by iksbob ( 947407 )

      Provided they settle on a deuterium/tritium fuel mix, yes.

    • Maybe. On the one hand, if 100% of our electricity comes from fusion, that works out to around 100,000-1,000,000 kilograms of helium produced each year. On the other hand, the amount produced per reactor at any given time is minuscule, and would be a pain to try to collect.

    • I don't know a lot of about fusion, but I've read Helium is a byproduct of fusion reactions. Once these things start getting run more and more, will we be able to harvest the helium generated to stave off the coming shortages?

      Yes, you have a cursory understanding.

      What people don't understand is that continuing this fusion for power kick will drastically alter ambient helium levels, and with that, the pitch of our voices! To answer your question, not only will shortages be reversed, but exponentially so, and to the detriment of our manliness.

  • by u19925 ( 613350 ) on Monday October 07, 2013 @08:17PM (#45065593)

    There are still three things missing:
    1. Scientists are only counting the laser energy absorbed by the fuel. Not all of the laser energy is absorbed by the fuel.
    2. Lasers are not 100% efficient. They take lot more energy than they give out.
    3. The generated energy is in the form of heat. Converting it to electrical is not there.

    Overall, the efficiency is still less than 1%. Far away from anything usable.

  • by gman003 ( 1693318 ) on Monday October 07, 2013 @08:24PM (#45065631)

    One of the big criticisms of the NIF is that the design is basically unsuited to capture more than a slim percentage of the energy released. It's good for weapons research because it works vaguely the same way a bomb does - rapidly compressing fuel in a burst. But it doesn't really have a mechanism for capturing that energy, unlike tokamak-based designs.

    Based on the summary (still reading TFA itself), it sounds like they broke even in terms of the energy input into the fuel being less than the total amount released from the reaction. But to be a self-sustaining, practical fusion power source, it needs to extend that two directions - first, by breaking even in terms of power into the entire system being less than that released, and second by breaking even in terms of power captured, not just power generated. The former is straightforward - more efficient lasers, more efficient reactions - but, and this is from a non-engineer's perspective, I don't think the latter will be simple.

    • by Khashishi ( 775369 ) on Monday October 07, 2013 @11:40PM (#45066651) Journal

      Tokamaks are far closer to practicality. In 1997, JET achieved 16 MW of fusion power with 24 MW of heating. ITER will almost certainly achieve much greater than breakeven. The goal is Q=10, where Q is fusion power/input power.

  • by Michael Woodhams ( 112247 ) on Monday October 07, 2013 @09:50PM (#45066163) Journal

    There are different ways to break-even.
    Scientific break-even means the energy you've provided to the fuel's environment is less than the energy the reaction liberates. This is what is claimed here, although even then they're squinting a bit by only counting the light absorbed by the fuel pellet.

    Engineering break-even accounts for the inefficiency in providing energy to the reaction (losses in laser beam generation and transmission, in this case) and inefficiency in converting the reaction energy into electricity (or other useful form.) Once you've reached engineering break-even, you have a facility which, provided with fuel, will provide you with electricity.

    Economic break-even is when the amount of electricity generated is sufficient to pay for the capital, consumables and maintenance (and perhaps waste disposal and decommissioning) cost of the facility.

    Incidentally, I thought magnetic confinement fusion reactors had reached scientific break-even a decade or two ago. I haven't found any support for this belief in a quick web search, so maybe I'm delusional.

    • by Phanatic1a ( 413374 ) on Tuesday October 08, 2013 @06:06AM (#45068225)

      You're not delusional. JT-60 in Japan sort of reached breakeven, but with one hell of a caveat: JT-60 only uses D-D fuel, but it achieved conditions in the plasma such that if the D-D fuel was replaced with D-T fuel, it would have achieved Q=1.25.

      What's delusional is the notion that ICF can ever be a commercial source of fusion power. Even after you squint and wave your hands and say "We reached break-even, if you count only the energy absorbed by the fuel," you need to realize the huge inefficiencies at every step along the chain. Conversion of electricity into laser energy is really inefficient. The IR lasers are frequency-converted into UV beams, a process which is only 50% efficient. And only about 10% of *that* actually goes into compressing the fuel.

      And that fuel is frozen D-T contained within a copper-doped beryllium capsule that needs to be spherical to micron tolerances, and the surfaces of that sphere need to be smooth to *nanometer* tolerances. The beryllium must be precisely 150 microns thick, and a 5-micron hole is laser-drilled through it. The capsule in turns rests within an equally-precisely made hohlraum comprised of a gold/uranium alloy. Each one of these precision assemblies costs tens of thousands of dollars to make, assembly of the various parts also must be done to micron tolerances. And out of this, if fusion works perfectly and every bit of the fuel is used, you can expect a maximum possible energy output of 45 megajoules. That's 12.5 kilowatt-hours of energy; if you can manage the miraculous feat of 100% efficiently converting that back into electricity, you could sell that electricity for about $1.25.

      For commercial fusion, they'll need to burn 15 of these targets per second, every second, indefinitely. Which means that in addition to needing a fusion gain factor of about *60* (compared to 20 for a tokamak, which will also probably never produce commercial fusion power), they'll need to get the fuel cost down to like 10 cents per target.

      Meanwhile, fission just works. Figure out how many LFTRs we could build for the cost of the NIF and weep. ICF is a jobs program for engineers who got scared as hell when the cold-war ended and started pimping their bomb-research machines to environmentalists who don't understand physics or economics.

  • by __aaltlg1547 ( 2541114 ) on Monday October 07, 2013 @10:37PM (#45066367)

    Or will I have to fire up the flux capacitor?

You know you've landed gear-up when it takes full power to taxi.

Working...