Is Fusion Power Going to Happen? Or Should We Just Hang It Up?

I mean, 50 years of research, and we seem no closer to a workable fusion reactor. The engineering problems (even assuming we can contain the reaction) are immense: structural materials will ail within weeks, we have no good way to extract the energy, and making a fusion reactor safe for extended operation. Our current technology has no answers to these challnges.
So, should we instead concentrate on making better, safer fission reactors?
If the Peak Oil gloom&doom folks ae right, we are going to have to replac a lot of fossil-fueled generation capacity-should we take the money spent on fusin research and make a big push into fission?

Have we not made any further strides in the fusion/fission hybrid technology? I thought I had read something recently that it’s being researched here in Texas.

Yes, this is the perfect time to give up:

National Ignition Facility

It’d be terrible if the nation achieved any energy breakthroughs on Obama’s watch, wouldn’t it, ralph?

Yeah, let’s quit trying to cure cancer too. Anything that takes that long can’t possibly be worth it.

Obligatory XKCD link that translates research predictions into non-technical English.

Squink, the NIF isn’t really intended as a demonstration of technologies usable for commercial fusion energy production. It is really more of an experimental tool to investigate fusion initiation conditions and the state changes that happen in that environment that cannot be adequately modeled via computer simulation. A significant amount of funding comes from Stockpile Stewardship and Management Program, which is chartered with maintaining the US Enduring Stockpile of nuclear weapons (i.e. aging surveillance, fault prediction, evaluating design enhancements, et cetera). The facility is slated for a number of experiments to support the Reliable Replacement Warhead, the first new nuclear weapon design since the end of the Cold War, and implementing all of the safety features that were incorporated into the W87 (originally carried in MIRV configuration on the LGM-118A ‘Peacekeeper’ ICBM, now redeployed on the LGM-30G ‘Minuteman III’ in single RV configuration) and the W88 (carried on the UGM-133A ‘Trident II’ Fleet Ballistic Missile). Although there may be experimental results that come out of the the INF, it isn’t intended to be a practical apparatus for nuclear energy production, and it is questionable that inertial confinement fusion can ever be a practical energy source.

The ITER on the other hand, is intended to advance the state of the art of sustained magnetic confinement fusion (tokamak-type reactor). It is not intended to be an energy production system itself, but rather to develop and demonstrate the technologies necessary to generate nuclear fusion energy production. These include not only the ability to sustain a fusion reaction for more than a single pulse of a few milliseconds (as the INF will do) but also to extract the power output in usable form and better understand and mitigate the effects of fusion reactions, such as bremsstrahlung losses, neutron embrittlement, and radioactivation of materials in the reactor. The advances from ITER are intended to lead to a demonstration reactor program called DEMO, and thence to commercial fusion energy production. The current planned operational dates for the ITER and DEMO are currently 2018 and ‘sometime in the 2030s’, leading to commercial fusion in the 2040s. However, this timeline has to be regarded as entirely speculative at this point, assuming that the multitude of problems currently known about tokamak confinement can be resolved.

Still, we know that fusion reactions work–one can see that by merely looking up in the daytime sky–and the general conditions required to achieve fusion are well understood. The development of controlled, confined breakover fusion for energy production is largely a matter of engineering (albeit, a very complicated engineering problem) rather than fundamental science. We can actually operate fusion reactors now–for a few thousands of dollars you can build one that will fit on your kitchen table and run off of 440V power–that don’t product positive net power production but do provide a neutron flux source that can be used to power a subcritical fission reactor that can be net positive as noted by Syntropy. That the previous promises of fusion power “in the next 20-30 years” haven’t come to fruition isn’t because it is fundamentally impossible, but because we lacked the analytical tools and empirical data to understand the magnitude of the difficulty and how to control the process finely enough to sustain a reaction.


Well, the much simpler fission reactor took quite a while too.

  • 1st nuclear chain reactor 1942 (Fermi, U of Chicago)
  • 1st nuclear electrical generator 1951 (US Atomic Energy Comm, Idaho)
  • 1st commercial nuclear generation plant 1954 (Soviet Union) or 1956 (England)

So depending on where you start counting (Kaproth, discovery of radium in 1789, or Becquerel, discovery of radioactivity of uranium in 1896, or Szilard, theory of nuclear chain reaction, 1933) you have either 162 years or 55 years or 9 years from discovery to a working commercial generator.

So I don’t think we need to give up quite yet.

What makes you think we AREN’T concentrating on making better fission reactors?

Well, we are. But we are also funding experimental work on possible fusion reactors. Why can’t we do both? Why must one exclude the other? The split of resources is by no means even, hence we are concentrating on the technology that currently works. But we can spare a few resources to advance science, even if that is all fusion studies accomplishes, it will be money well spent.

Well, as I said, can we determine at this point, whether the engineering problems are solvable? like, under the expected neutron flux produces, are there any metals that can withstand it?
We know how to make relaible fission reactors. If we determine that fusion isn’t feasible, it would be prudent to go ahead and design advanced fission reactors.
or maybe the peak oil people are wrong!

What’s the point of hybrid reactors? If I understand it correctly, the idea is to use the high energy neutrons released by fusion to fission U-238 (the cheap common isotope that only fissions from neutrons with very high energy). How is this an improvement on just building breeder reactors?

Breeder reactors are, by nature, marginally stable or unstable, as they require high energy neutrons rather than thermal neutrons. The composition of the fuel is also very specific and requires constant reprocessing in order to keep the pile within an equilibrium state. It is the expense and waste of reprocessing, rather than the operation of the reactor itself, that makes breeder reactors currently not fiscally viable. On the other hand, hydrid reactors use an external neutron source (typically some kind of electrostatic fusor) from which the neutron flux can be readily controlled, and in any kind of emergency it can be just shut down by simply powering it off, which will rapidly curtail nuclear reactions.


This (or that ?).

Though my opinion is that breeders are more a pain than at an actually unworkable level. Hybrid reactors deserve much more research for sure.

Back to the OP. IMO fusion research should continue, but honestly, given what we can do now, even if aliens showed up and said convert to 90 percent fusion power in 40 years or we will exterminate you I don’t think we would have a good chance of surviving.

There are just so many big and little problems with fusion to get it to WORK. And then god only knows how many problems we may find once its “working” on a large scale.

With regular nuclear fission, we have 10s of thousands of “reactor years” with dozens of various designs. We know what basically works. We already know many of the pitfalls. We still have plenty of ideas to try that may make it easier or safer or cheaper than it already is (and IMO its acceptably all of those already).

Fusion may be the ultimate power source, but fission is doable, expandable and moderately improvable RIGHT NOW. At the very least, it will buy us a few hundred to a few thousand years more of affordable and workable power. Plenty of time to get all these other power sources to a workable level if its possible.

IIRC we actually do not have all that much uranium for fission. I was reading something that suggested at a 10TW level of generation there is about 30 years worth of proven uranium to be had.

So, we either need to find more uranium or continue with fusion research (I believe fusion reactions can be used to manufacture uranium for use in a fission reactor but not sure how feasible it is). Lets you skip the Breeder Reactor as well.

Thats PROVEN reserves.

Unproven is many multiples of that most likely.

Then there is the stuff dissolved in seawater, which IIRC can be extracted at about 10 times what the mined stuff cost (and as a bonus you probably get a shitload of “free” clean, fresh water). Given that the cost of uranium is nearly in the noise when it comes to the overall cost nuclear power, expensive sea water uranium aint going break the bank.

Then you got multiple shit loads of thorium you can use in a nuclear cycle (another fission power area deserving much more research).

There are real issues with nuclear fission power, but IMO lack of fuel aint remotely one of them.

As a bit of an aside I was reading that link and they say the new laser puts out 1.8 megajoules of energy.

Sounded like a lot so I looked it up here and it says a megajoule is equivalent to 0.2168224 kilograms of TNT.

Err…what am I missing? That seems like near nothing to achieve a fusion reaction.

Its **that **much energy deposited on something the size of a BB in a tiny fraction of a second.

ralph124c, YOU are the one to foresee.

Okay, that was cute. Nice one.

Laser fusion test results raise energy hopes

Peak oil is about running out of oil and natural gas to power transportation. Fusion wouldn’t make a difference in that.

But the fact that fusion isn’t cost competitive yet doesn’t mean it never will be. There is enough potential energy in wind, solar, geothermal, fission, etc to power dozens of human civilizations. And energy demands only go up 1% a year in the developed world (3% a year in the developing world). So grid electric really doesn’t seem to be a problem.

I was rather surprised when Obama mentioned fission power in his SOTU address. I guess he’s decided, who else are the Greens gonna vote for anyway?