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.'"
bbc? (Score:5, Interesting)
why is the bbc first to report on this? It happens in CA, and we get scooped? wtf??
Comment removed (Score:5, Interesting)
What controls the ceiling of the energy output? (Score:0, Interesting)
Honest question since I am not a physicist.
What controls the ceiling of the energy output on something like this?
Let's say they have an accidental breakthrough, and suddenly they're getting more out of this thing then they get in. What determines the limit of the maximum energy output? What determines the rate at which that energy is produced? What would something like this look like if the reaction got out of control? Would the experiment just explode, or would it start glowing red/yellow/white hot?
Helium? (Score:4, Interesting)
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:bbc? (Score:4, Interesting)
US news agencies are busy covering government shutdown.
$200 per pound = millions of tons of coal (Score:5, Interesting)
The RESEARCH is expensive. The base fuel comes from seawater and costs hundreds of dollars per pound. The energy in one pound is equal to millions of pounds of coal.
Even better, most of the fuel cost is the energy needed to separate the fuel from seawater. With self-powering desalination / fusion plants, fuel cost would be pennies.
The difficulty is that conditions have to be just perfect to keep the reaction going. If anything isn't just right, the process stops and you're left with what looks and acts like a baby aspirin. That's awesome for safety, though. That's the opposite of fission, where they are trying to keep a naturally volatile reaction under control.
Re:bbc? (Score:5, Interesting)
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.
Three things missing... (Score:5, Interesting)
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.
Re:Holy fucking shit, this is AWESOME. (Score:5, Interesting)
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.
Scientific "break even", or practical "break even" (Score:5, Interesting)
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.
Re:Holy fucking shit, this is AWESOME. (Score:4, Interesting)
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!
Three levels of break-even (Score:5, Interesting)
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.
Re:Scientific "break even", or practical "break ev (Score:3, Interesting)
I think this is a decent milestone. While the reactor design itself is unlikely to ever break even, hopefully they're at least learning enough about efficiently triggering a fusion reaction that they can apply it to more productive designs
This achievement opens the door for future designs. Inertial confinement works; it needs improvement, but we're no longer debating whether it's possible to maintain symmetry or any of the other many doubts the detractors dwelled on.
The haters of NIF — and there are [nrdc.org] many — won't permit followup; they'll have it shut no matter what. For them, the whole idea of seeking energy sources that don't demand energy poverty is inherently illegitimate, and they run the show now. But the work and the results won't die at LLNL; there are other people and other nations that haven't decided to turn themselves into a windmill powered nature preserve.
So we'll have to let them take the ball and run with it [ucsd.edu]. At least it will continue, now perhaps with far more enthusiasm.
Re:because it didn't matter (Score:5, Interesting)
Why? Nobody else does.
Coal is considered as present in the boiler - no taking into account powering sootblowers, crushers, conveyors, trains and actually getting the stuff out of the ground. That total consumption is not so easy to work out and will vary widely anyway.
Nuclear does the same thing and starts with the assumption that fuel rods appear by magic, which although dishonest is understandable if they are comparing it with coal in the situation above.
This is cutting edge stuff and we're only now getting the first of the 1980s design of the AP1000 nearing completion - "commercial use" is not going to be a consideration for a while no matter how good it is. It takes a lot of work to turn a breakthrough into a commodity.
Re:bbc? (Score:5, Interesting)
Doubt it. Light pressure is what compresses and heats the fuel.
Not true!
The lasers only irradiate the inner walls of the hohlraum which generate X-rays. When those X-rays are absorbed by the outer wall of the hohlraum, it implodes and compresses the fuel.
Light pressure would not be uniform enough to generate a uniform compression profile.
Re:bbc? (Score:5, Interesting)
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.
Re:bbc? (Score:4, Interesting)
"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.