> 3. Extracting useful energy would require capturing hot neutrons in a "blanket", heating it up, and running fluid through it to boil water to drive a steam tu

> 3. Extracting useful energy would require capturing hot neutrons in a "blanket", heating it up, and running fluid through it to boil water to drive a steam turbine. The minimum practical size for such a "blanket" exceeds that of a large fission plant. To collect enough neutrons to be useful requires a huge volume of plasma, as even compressed plasma is very diffuse vs. fissiles. I worked as a control systems engineer in the nuclear power industry for 8 years back in the '90s. I worked on Lungmen in Taiwan, ABWRs (Kashiwazaki 6/7) and even Fukushima (power uprates) in Japan and Grand Gulf and Pilgrim in the USA. Fusion is billed as a "clean" alternative to fission reactors but I think this is (another) false hope of the technology. I still recall my nuke prof telling me that fusion (if it ever works) is going to be an even bigger waste problem than fission reactors. The 15 MEV neutrons are going to neutron-activate tons of shielding or heat extracting blankets which would be a huge disposal problem. He also thought that neutron embrittlement of plant structures was going to be a serious problem and is already a problem in fission plant cores that use thermal neutrons. Carting that waste away at EOL will kill the economics. We should start building fission plants now which are safe and clean enough and can provide power until something better comes along.