Fusion power could arrive sooner than expected
extremetech.com
extremetech.com
Actually, the 15 years out time frame puts it beyond what I've expected, 10 years out. That's where fusion has been for most of my life, 10 years from now.
PS: I have heard that the real issue was scaling up Jet was assumed to be work but doing so was to far from commercially viable to be useful.
(extremely speculative of course)
2. Ideas for parallel implementations of nuclear fusion have expanded, and as a result, funding and research has arguably become fragmented and resources have been diverted. In reality, there's a fixed amount of capital and knowledge (which is also a function of the availability of money) available for this kind of research. The amount of money the US puts into fusion research is quite paltry compared to the potential benefits. It may be a priority, but the way Washington spends money says otherwise.
Scientifically, fusion is maybe 10 years away. Politically, it's more like 40 for a real power plant, but with the current congress, I couldn't say. In addition to that, it's an expensive enough endeavor that it would be corporate suicide for a private company to attempt it, especially considering the majority of companies with enough capital to pursue something like fusion tend to be in the Oil and Gas industries.
Tri-Alpha has over $90 million in venture capital, some from Paul Allen. General Fusion has about half that, with Jeff Bezos as an investor. LPP is a lot smaller, but also doesn't need nearly as much at this point.
There are several other approaches in the works that could conceivably by privately funded, including Helion (needs $20 million for a full-scale reactor, already built a 1/3 scale version) and petawatt picosecond laser fusion (once the lasers get a little better).
Another promising approach is levitated dipole, but I don't know what costs look like for that one.
But we lack the infrastructure and investment to build them.
Francesco Celani's experiment is being in a process of replication: http://youtu.be/Q2qWgh7Gx4g http://youtu.be/gHpYuUykWw0 http://youtu.be/qc5RoGg6n8E http://youtu.be/HN4VK82Mngc
Please, please - at least watch this video: http://youtu.be/26k3Cz3wW-8 -> This is a great initiative.
Folks, the clean controllable energy source out of LENR process is almost here. Please go through my links with an open mind and consider sharing them with your family friends and colleagues...
What happens if they get just a little above break even?
They have several other tests to do and plan to do a complete test by the end of 2013. If it still works the way their simulation predicts, they'll approximately hit breakeven.
The next step will be to build a machine several times bigger. According to the sim, that would take us from breakeven to a 100x to 1000x energy gain (depending on how powerful they make the machine.)
Such a large gain helps a lot for turning it into a practical plant. For one thing, they'd only have to fire a shot every ten seconds or so. NIF's laser approach, by comparison, would require ten shots per second.
I don't know all the ins and outs, but it's important to understand that the big US experiment in nuclear fusion was NIF, at LLNL. They (perhaps rashly) promised net energy gain by the end of this fiscal year. This whole thing was part of an elaborate political deal regarding maintaining nuclear expertise during the test ban treaty.
Anyway, net gain did not happen; the ratio of energy out to energy in at the NIF is 0.1. This had been expected for many months now (indeed, it was predicted by some as soon as the deal was cut, years ago.)
At this point, the pie of nuclear research dollars is going to be re-cut with different allocations. For one thing, the fusion/non-fusion balance at NIF is going to tilt away from fusion.
So, in the absence of a NIF fusion success story, this press release could be part of a campaign by other labs or other experiments to press their own research agenda for fusion.
For partial background:
http://www.nytimes.com/2012/09/30/science/fusion-project-fac...
Amongst the many attractive properties of LFTRs is the ability to burn spent fuel from existing nuclear plants.
Less dirty than fission, absolutely. Enough less dirty to make it manageable in a way that fission doesn't seem to be, more than likely. But not clean.
Any material in and around the reactor becomes nuclear waste in the same manner as it does for fission: by getting blasted with high-energy particles until it becomes radioactive. And while there wouldn't be any spent fuel rods to deal with, one of the products of hydrogen fusion, tritium, is also a source of concern.
Isn't tritium a nuclear fuel?
By any measure, cleaner than what else is out there. Already a fission nuclear power plant will produce less leakage of radioactivity into the environment than many coal plants, fusion drops that level several orders of magnitude more.
First off, no fission products, which are typically the most dangerous radioactive waste from fission reactors. Second, the materials used in the reactors don't have the same engineering constraints that fission reactors do and so can be chosen to produce far lower quantities of hazardous radioactive isotopes bred from intense neutron flux bombardment. Also, Tritium is a fuel, and of enormous value so it would be handled very carefully. More so, it would be bred specifically in custom built containment vessels within the reactor.
On top of all that you have the fact that a fusion reactor cannot be made to undergo a meltdown or overload the way a fission reactor can. If something bad happens in a fusion reactor the immediate result is usually that fusion stops, which compares very favorably to the what happens in a fission reactor: fission chain reactions continue, temperatures build as the heat from fission products decaying builds up, etc. And you don't have weapon proliferation concerns.
Overall what you have with nuclear fusion reactors is no chance of a meltdown, very much less hazardous waste generated (by orders of magnitude) and a very clean energy profile.
Sorry for the highlighter attack, but fusion still means building extraordinarily complex and expensive reactors that are going to have one hell of a carbon footprint and shed tons of radioactive waste in normal operation.
Let's roll it back to "potentially cleaner in some key ways".
Let me make it as clear as possible. Fusion energy is fundamentally safer and cleaner than fission energy, period. Firstly, it is simply not physically possible for fusion energy to generate even a tenth as much of the radioactive waste as an equivalent fission power plant. Secondly, it is not possible to have a dangerous power excursion at a fusion plant. When a fusion plant malfunctions it doesn't experience a runaway reaction, it stops working. If a fusion plant experiences some sort of catastrophic structural failure everything stops. This is in stark contrast to fission reactors which can undergo continued fission chain-reactions even if, and perhaps especially if, the reactor vessel is disrupted and the fuel melts down and also produce fission byproduct isotopes which continue to generate enough heat after the fission reactions have stopped to melt the reactor core if it is not continuously cooled.
Also, there is little evidence that the construction of a fusion reactor would entail a higher energy-usage footprint than a fission reactor, and the lack of a need for massive reinforced concrete structures in a fusion reactor tends to argue that the footprint would be rather less.
Let's roll it forward back to: undoubtedly cleaner if it can be made to work.
Granted: Fusion energy is a conceptually simpler process that is virtually impossible to runaway by its very nature. That alone is a massive plus any way you look at it.
Granted: the total bulk volume of radioactive waste products is dramatically lessened.
Granted: the radionuclides created by a fusion reactor are likely to be less problematic than those from a fission reactor.
My points: There is still radioactive waste: magnetic confinement reactor liners will handle so much corrosive flux they'll essentially be disposable and replaced frequently - possibly on the order of weeks or months. Same (but lessened) story for inertial confinement reactor liners and the metallic waste products. Those have to go somewhere safe. They're not small.
Same story for the electrical generation system. Regardless of the final reactor type, it's still going to involve managing heat-exchange fluids with neutron exposure.
Then there's the environmental + carbon load from building a reactor complex, which is not going to be quantifiable until there are working reactor designs and working fuel flows and a working understanding of how much staffing and security and land and ancillary support is needed. NIMBY is going to be just as strong for fusion as it is for fission, and that's going to mean compromises.
Then there's going to be the cost of purifying the fuel source, which won't be negligible when it literally involves boiling the seas. Then packaging it. Then shipping it. Then handling the waste products. Then planning for the plant's functional lifetime, which won't be forever.
The conceptual clarity of fusion is wonderful and I fully support the research, but the execution is going to be quite a bit less sexy and come with some well-known downsides.
The sun is a 100% fusion reactor.
If you mix a fusion and a fission reactor, probably you will have most of the disadvantages of the fusion reactors; in particular you will have a lot of long-living radioactive byproduct of the fission reactions.
Detonating a nuclear weapon inside of a power plant isn't really practical. :-) Existing nuclear power plants don't get anywhere near the temperature and pressure needed to start nuclear fusion.
So, now we have the engineers trying all sorts of ways to get to the needed temperature and pressure without turning the plant into a smoking crater. That's where all the fancy lasers and magnetic pulses described in the article come in: They're trying to aim the heat source so they can superheat the fuel without melting the containment vessel.
For instance, the test version of the Tsar bomb had its last fission stage removed, reportedly resulting in a 97% fusion detonation. Of course, those still cause a huge lethal neutron flux, but at least the amount of fission material released is pretty small in relation to the overall power of the device.
Here's how combined fusion/fission plants would theoretically work:
A fusion reaction is used to create a large quantity of high-energy neutrons. These high-energy neutrons are then used to cause fission in an otherwise subcritical fission assembly with extremely low enrichment fuel. 'Natural' uranium (U-238) is fissionable, which means that it can undergo fission in the presence of /high energy/ neutrons.