Reply To: Repowering the electric utility industry

[BSFusion]

And Bubble-confined Sonoluminescent-laser Fusion (BSF) certainly doesn’t have any issues, since it only exists on paper. Not enough research on a practical device has been done to even confirm how thick this blanket might be since the laser would have to traverse it too. Nor do we know the energy level and penetration power of these neutrons leaving the bubble reaction. Too slow or too fast, and they won’t interact with the heavy water (deuterium) to make Tritium. Nobody has even confirmed real fusion reactions taking place. So far, some of the scientists working on it, have resigned that the temperatures needed for fusion could not be reached using bubbles.

BSF is still quite hypothetical.

Jo…, In BSF, external lasers do not have to transverse the blanket, the coolant material of the blanket resides inside of a spherical laser cavity, and, after that material is pumped into a state of population inversion, it functions as gain medium, just like in any other liquid laser. In the context of BSF, two coolant mixtures were examined, Li2BeF4 and a randomly chosen glass mixture having the formula (SiO2)50(PbO)10(Li2O)30(Nd2O3). The mean free path distances for 14 MeV fusion neutrons, traveling at approximately 15 meters per microsecond, were calculated to be, 7.14 cm and 5.95 cm, respectively. I think you are still confusing BSF with sonofusion; BSF does not use deuterium in heavy water to produce tritium, it uses Li in molten glass (or FLiBe), and BSF uses a high energy laser to ignite the fuel, acoustics play an insignificant role – they are only used to pre-compress the fuel and trigger the initial laser cascade. What scientists are you talking about? I’m the only person working on BSF.

So, to be clear, would a pB11 FF reactor definitely need shielding to be around humans, or not?

For a p-11B FF reactor, in addition to neutrons, large quantities of hard X-rays will be produced by bremsstrahlung, and 4, 12, and 16 MeV gamma rays will be produced by the fusion reaction. Shielding from gamma rays requires large amounts of mass, in contrast to alpha particles which can be blocked by paper or skin, and beta particles which can be shielded by foil. Gamma rays are better absorbed by materials with high atomic numbers and high density, although neither effect is important compared to the total mass per area in the path of the gamma ray. For this reason, a lead shield is only modestly better (20-30% better) as a gamma shield, than an equal mass of another shielding material such as aluminium, concrete, water or soil; lead’s major advantage is not in lower weight, but rather its compactness due to its higher density. Protective clothing, goggles and respirators can protect from internal contact with or ingestion of alpha or beta particles, but provide no protection from gamma radiation from external sources.