Alternator Design NERD FOOD Look At Your Own Risk

I did work for a company that designed a 4.5 KW alternator. That's 375 amps at 12 volts, although it was a 48 volt design IIRC. It was a permanent magnet design with separately wound poles instead of the "claw" pole design of most modern alternators - much more efficient and about the same size as my vehicle alternator. It cost $5-$10 more in quantity than a conventional alternator.