How do we approach optimizing and scaling up from FF1? If plasma must be filamental to generate a DPF must we have a cluster of FF1 devices to achieve commercial scale? Or can multiple filaments be generated within a larger device more or less simultaneously? If the heating electrons can be more efficiently absorbed by multiple DPFs occurring in rapid succession, can the collapse of multiple magnetic fields be controlled?
The current concept of scaling up is to use multiple dpf units. That way one unit could be down for service while other units carry the load. The units would be deployed in a network similar to cell phone towers. This gives the energy network great resilience in case of natural disasters or sabotage. The cost of long distance distribution systems would be reduced.
As a practical matter, each unit produces a lot of heat in a very concentrated volume. That heat has to be removed fast enough to prevent the electrodes from being damaged. Some of these engineering concerns will be better known when the FF1 unit produces significant power.
At the moment only 20% of the heating current is absorbed by the DPF plasma. So there is opportunity for efficiency by either decreasing the rise time or adding DPF filaments within the rise time of the current. I agree that cooling is a problem, and have doubts that the X-ray absorbing “onion skin” will help.
What we need to do is see what is possible, then do the engineering.
AS has been mentioned, a lot of heat may be generated in the onion by both photoelectric and ohmic losses. Also some heating will occur in the inside surface from alpha and light irradiation. Is it possible to make the onion a PETE (photo enhanced thermionic emission) device?