OK, I may be missing the point but it sounds like Nigel has gotten distracted by technical issues.
What he seems to have, is a 10-hp permanent magnet
motor, very similar to the ones used in the lunar rover in 1969, but this one is being used in reverse as an AC
generator. (Generator,
alternator, potato, potatoe.) PM motors have taken over the cordless drill, etc. market in the last five decades, as the prices of powerful magnets have come down, and the prices of copper (for conventional coil windings) has skyrocketed. I'd suspect there have also been heat issues with using them in the automotive market, since heat ruins the magnets.
And that 10hp
motor is being used to produce up to 555A and 14.4 volts, a damned powerful
alternator.
It sounds like the box with the "planar transformer" (think flat plate versus cylindrical battery plates, planar transformers are simply better at high frequency and
power, they're nothing new) is oretty similar to an
MPPT controller for the
generator. That's the only way to take the varying voltage from a varying speed generator and turn it into a steady DC output.
All the rest about tying into an engine's computer monitoring system, well and good for new boats but possibly a total stopper for "plain"
boat engines. You'll notice that's not addressed.
As to how the magic box accounts for
engine load...All that it CAN do, is to
monitor the engine's electronic sensors (if there are any, remember) and then to basically "turn off" the
MPPT functions, stop putting a load on the generator, when the
engine is overloaded.
If the system is priced right and built well, it sounds like an intelligent way to produce
power. Way smarter than our pre-WW2 automotive technology.
But that video has way more sizzle than steak. I'm very much surprised at that.