I very much like the idea of a hybrid fusion-fission reactor such as the concept described by the physicists at University of Texas Austin. It would serve not only as an energy source but would also use spent nuclear fuel from fission reactors helping to clean up existing nuclear waste.

I was no doubt guilty of this before I became a physics researcher but I want to be very clear about a few things. Please do not take this as an insult people… I learned this myself at one point at a time I was misinformed to believe certain things were givens.

1) Fusion is not inherently clean. In fact, per watt it produces far more neutrons than Fission (in addition to the usual gamma rays). This means more neutron activated materials. Bombarding almost anything with neutrons that is already stable results in something radioactive. Believe it or not it is a LOT more trouble and expense to deal with large amounts of low level waste safely compared to a small amount of high level waste.

2) Most importantly there are never guarantees in research about when something will happen. The reason that applies here is because I have yet to speak to a single nuclear physics or nuclear engineering professor who has not rolled their eyes in frustration at how determined the public is to believe that economically viable fusion is “just around the corner”. We have yet to do anything but dance around breaking even as it is. It is of course possible that it is just around the corner the same way anything is possible… but right now the endless difficulties of high temperature plasma dynamics that keep cropping up are not showing signs of going away. In fact the people I have spoken to who have spent their careers studying it have said the more they learn about it the more unpredictable it proves to be.

Please for the love all things good listen to actual nuclear physics and nuclear engineering organizations. Not individuals, as a single scientist can never speak for us all… even though a few do either to sell a popular book or get public support for a theory they cannot get informed support for. The amount of money that continues to be thrown at fusion is absurd in the estimation of practically every other physicist I have ever known… professor, postdoc or grad student. Same goes for nuclear engineers. PLEASE listen to us.

Just as an FYI, a Fusion-Fission hybrid shows incredible promise considering you could make a source of neutrons that took more energy than it gave and still generate a tremendous net amount of energy. Fusion increases Fission (by adding neutrons than can be moderated) but Fission does not increase Fusion (Fusion requires heat on the order of 10-100 million Kelvin, 10 million for the core of the Sun, and 100 million for if you need it to happen in a less astronomically macroscopic setting).

John says: “Fusion fuel is not plentiful; it’s not found in seawater. Tritium must be made in a reactor and has a 12.5 year half life.”

The methods employed for tritium production are decided by end use and quantity demand. Many or most modern nuclear weapons are “tritium boosted.” The 12.3-year half-life of tritium makes it impossible to store tritium gas boosted weapons for decades without replenishing the tritium. US-Russia arms reduction agreements had the US removing tritium from deactivated weapons to replenish weapons still in inventory.

During the Cold War the US produced most of its tritium by neutron bombardment of heavy water in special built fission reactors located at the Savannah River National Laboratory in SC. These reactors were shut down in 1988. US tritium production ceased for the next 15-years, but resumed in 2003 at the Watts Bar Commercial Power Station, where special moderating rods containing lithium 6 were installed. By 2006 enough lithium 6 in moderating rods had been converted to tritium that the new tritium extraction facility at Savannah River could again begin US tritium production. Upon detonation, modern high-yield nuclear weapons “breed” tritium out of lithium-6.

But tritium for commercial fusion reactor fuel would come from a different source that is more like the Watts Bar program. A “blanket” of lithium 6 would surround every tritium/deuterium fusion reactor. The operating fusion reactor’s neutron flux would constantly interact with the lithium blanket to “breed” more tritium than the reactor consumes in power production. Initial planning suggests every fusion power plant would have its own tritium extraction facility that would employ the Savannah River process to constantly remove the freshly bred tritium from the lithium. So for all practical purposes, there would be unlimited supplies of tritium for fusion reactor fuel. The question is not where to get the tritium, but rather where to get the fusion reactors.

There are actual working small-scale prototypes of the Bussard Polywell system, which is similar to Eduardo’s system in many respects. The US Navy is parsimoniously funding the Polywell development project, and insuring that public reports of results are meager. The most interesting characteristic of the Polywell system is increases in scale yield energy output by the fifth power of size increase. See: http://en.wikipedia.org/wiki/Polywell and: http://newenergyandfuel.com/http:/newenergyandfuel/com/2012/05/11/more-time-and-funds-for-bussards-iec-fusion/

“Bussard calculated that a Polywell reactor with a radius of 1.5 meters would produce economically viable net power using (2H+2H ) reactions.”

Present incarnations of EMC2 lab prototypes are now up to generation 8, and empirical testing shows that Bussard’s scaling formulas are indeed valid. Enough research and testing has been done on Polywell to develop high confidence in the proposition: To date, this seems by far the most promising and rapid route to commercial fusion power. It will be a lot more complicated and costly than we would like (or that its promoters will disclose), and certainly nothing as elegantly simple as just mixing hydrogen with nickel powder, but it would have the major advantage of actually producing commercially viable “excess” energy by fusing deturium atoms by mechanisms consistent with the well-settled laws of nuclear physics.

Hi John,
You are right about tritium. My error. Deuterium is abundant but tritium is a byproduct of current fission reactors.
Len

Deuterium does match the availability claims, but the notion that D-D fusion is on the way would make the most ardent NIF supporter laugh.

MagLIF is a technology I overlooked….oops. From what I have quickly gleaned through an online search, the technology is described as magneto-inertial fusion (MIF). It is described as a pulsed fusion approach that uses a laser to preheat the magnetized fuel contained within a strong magnetic field. Less compression is required to get the fuel to the appropriate temperature where fusion can take place. MagLIF uses a mixture of deuterium and tritium. Currently a product in the lab MagLIF could achieve near break-even energy results in the 2017 timeframe but commercial operation is probably two decades away. For more information see http://fire.pppl.gov/IFE_NAS_MTF_Wurden_2pager.pdf.

Thank you for making our readers aware of your patent pending technology. Visit http://www.crossfirefusion.com/nuclear-fusion-reactor/crossfire-fusion-reactor.html to better understand the concept. From what I understand the theory is that using 6-superconducting magnets creates a more focused plasma field and faster positive energy output yield rates with lower energy input. The questions I have are: Is this more than a concept – that is, has a lab version been built with data results showing multiples of energy yield versus energy input to initiate the plasma field? Is the application of this type of fusion reactor for usage in propulsion systems for space travel or Earth-based for domestic and industrial use? What kind of energy output is possible from this device? Can it be scaled?