I saw the wiki poage was updfated a few weeks ago after a very long period of practically no news. Great times. Philo would be proud; the Tokamak folks still don’t have a usable neutron source and he built one 50 years ago.
I still have not grasped how the power is to be reliably harnessed though. Still way off IMO, but visible as opposed to the tokamak boondoggle.
If the polywell runs one of the neutronic fusion cycles (D-T, D-D), it will extract energy just like the ITER (i.e neutrons lose energy in a moderator---like water--heat up the water, make steam, and drive a generator). This is limited by the Carnot cycle, but no worse than a fission reactor or other fossil fueled power plant. The large number of neutrons tends to "make things radioactive", so there will be some radwaste associated with the process.
If they succeed in running one of the higher energy aneutronic fusion cycles (PB11), then they can design the electrostatic confining fields to "leak" ions at a specific point and do magnetohydrodynamic conversion by "slowing down" the high energy particles, which can be up to 80% efficient.