I just want to address the price thing again. And hopefully simply. Consider the US electricity production in a year – around 3500 TW.
The mass of Boron-11 needed to accomplish this energy can be found.
(3.5×10^15) kWh / ( 8 MeV ) * 11 amu = 180,000 kg = 180 tons
We’ll say 400 tons for energy conversion efficiency.
Even the absurdly high price of $2 / g would translate into $2000 / kg and $2 M / ton.
That comes to $ 800 M to power the USA for a year.
Current oil imports run around $ 600 B / year. The entire power industry is also of that magnitude.
With conservative calculations we see 3 orders of magnitude cheaper than current energy.
p-B fuel is simply free. Free in the sense that it’s so cheap it’s completely out of the picture compared to the other challenges.