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If Fusion Is the Answer, We Need To Do It Quickly
Lasrick writes: Yale's Jason Parisi makes a compelling case for fusion power, and explains why fusion is cleaner, safer, and doesn't provide opportunities for nuclear smuggling and proliferation. The only downside will be the transition period, when there are both fission and fusion plants available and the small amount of "booster" elements (tritium and deuterium) found in fusion power could provide would-be proliferators what they need to boost the yield of fission bombs: "The period during which both fission and fusion plants coexist could be dangerous, however. Just a few grams of deuterium and tritium are needed to increase the yield of a fission bomb, in a process known as 'boosting.'" Details about current research into fusion power and an exploration of relative costs make fusion power seem like the answer to a civilization trying to get away from fossil fuels.
Why would they need to create a new hate conflict? There's plenty of that to go around as is. Arab vs. Jew, black vs. white, East vs. West...it's not like conflict wasn't around before banking cartels, you know.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
Right now we have some issues with materials and reactor designs, but the basic physics are in place and understood.
The basic physics was in place and understood in 1952. They just had some issues with materials and reactor designs.
Look at ITER: $20B and rising, it will only make 500 MW(th) -- six times less thermal energy than a 1 GW(e) fission reactor -- and it doesn't even include the advanced materials needed to withstand commercial reactor levels of integrated neutron flux.
Well, that's ITER's point now isn't it? We know what is required to make fusion work, we just don't know how long we can sustain a reaction because we do not understand how the large neutron flux will affect the materials in the container and we still have difficulties maintaining the containment. It's an engineering problem now, not something that is clearly impossible.
IMHO, investments in such experiments should be expanded, by both government and industry. Just like getting a man on the moon, We need a JFK'esk commitment to making this work.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
That has to be one of the most misguided ideas I've ever seen...
Worry about using deuterium and tritium being used to boost the output of a fission weapon is like worrying about whether a heavily armed maniac's getaway car can do 120mph rather than 115mph. The basic problem isn't the speed of the get away car. If a proliferator can get their hands on sufficient U235 or Pu in the first place, they're 99.99996% of the way towards their goal - the extra .00003 provided by the availability of deuterium and tritium is all but meaningless because when it comes to proliferators it's the mere fact that they have a weapon in the first place that's the problem. That they can now build two or more, or increase the yield of a single weapon simply doesn't count for much when even a low kiloton range weapon is sufficient for their needs. (Which is deterrence generally, or failing that attacks against non military area targets. They aren't trying to crack open Cheyenne Mountain.)
Well, since the whole purpose of fusion reactors is to make commercially useful power, it is pretty clear that we do not have a working fusion reactor by any reasonable definition.
Despite having spent billions (22 Billion USD on hot fusion research by US alone) on the problem so far, with billions yet to come, we do not have working fusion reactors. Even ITER will just be a prototype with no power generation at all. Cost to develop commercially, unknown but bound to be a lot of money.
The US alone has also spent around 15 Billion developing Fast Breeder reactors, and has little to show for it. Other countries have similar experience.
Estimated cost to develop commercial LFTR reactors seems to be in the range 3 - 20 Billion USD. A commercial LFTR prototype seems to be likely 1 billion USD by most observers.
And you still have to build the reactors -- that won't be cheap either. Every known possible solution to replacing our energy infrastructure has a large economic cost, and significant to large environmental cost as well. Kind of the way large-scale engineering works.
Yet the cost of doing nothing will be larger yet, at least eventually. Peak fossil fuel is coming sooner or later, even if you master shale and methane hydrates with high recovery rates and limited environmental impact. There are a lot of third-world people in this world that would gladly join the first-world lifestyle which puts a severe constraint on expanding fossil fuels usage to match the growth in demand.
Personally, the combination of LFTR and renewable sources seems most likely to me to be commercially successful by 2050. Why, because the needed development seem to be within or nearly withing the capabilities of current engineering in both cases. Engineers are very happy to deliver good enough when the perfect seems unattainable.
You're arguing against Tokamak fusion. But what about, say, HiPER? Looks to me to be a much more comercializeable approach, yet it's still "mainstream" fusion, just a slight variant on inertial confinement ala NIF to make it much smaller / cheaper / easier to have a high repeat rate (smaller compression pulse + heating pulse rather than a NIF-style super-massive compression pulse). The only really unstudied physics aspect is how the heating pulse will interact with the highly compressed matter; NIF and pals have pretty much worked out the details of how laser compression works out. Beyond this, pretty much everything else is just engineering challenges for commercialization, such as high repeat rate lasers, high-rate hohlraum injection and targeting, etc.
I've often thought (different topic) about how one can get half or more of fusion's advantages via fission if you change the game around a bit. Fusion is promoted on being passively safe (it's very hard to keep the reaction *going*, it really wants to stop at all times), it leads to abundant fuel supplies, and there's little radioactive waste (no long-term waste). But what about subcritical fission reactors? Aka, a natural uranium or thorium fuel target being bombarded with a spallation neutron source. Without the spallation neutrons, there's just not enough neutrons for the reaction, so the second the beam gets shut off, the reactor shuts down, regardless of what else is going on. It'd be a fast reactor, aka a breeder, aka, your available fuel supplies increase by orders of magnitude. And your long-term waste would be much, much less in a well-designed reactor. Spallation neutron sources have long been proposed as a way to eliminate long-lived nuclear waste by transmuting it into shorter-lived elements.
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?
The main problem they had with materials is that they couldn't source enough of these small, green, flexible rectangles that they could exchange for almost anything - building materials, labour, research effort, rent, food, etc.
What a load of bull. Only in the core of the Sun does fusion actually occur. The temperature at the core is 15 million Kelvin and the central density is 160,000 kg/m^3. That is an energy density fucking orders of magnitude about decomposing manure. The numbers you get are by averaging over the entire Sun, which is irrelevant, because only a tiny central region of the Sun is hot enough for fusion.
10+ years on Slashdot and in the past few years it has really been taken over by amateurs. Every hard physics / astronomy article is filled with nonsense patently FALSE comments modded up to +4. Our collective intelligence has been decreasing, friends.
Please know what you are doing before you mod up an incorrect article... a simple Wikipedia peek will fix it for you folks.