60v alternator, electric supercharger...

[Seth Allen]

Now this is just daydreaming, but I have used an alternator powered 
stiock welder, and if I remeber right, it was about 60v, may be more at 
about 3000 rpm on a GM van. That should be good unough to charge a pile 
of nicads  at a high enough voltage to reduce some I^2 R losses.  Maybe 
72v is possible, especially with a maximum power point tracker, like they 
use to charge 72v battery piles from varying, but low voltage solar 
arrays for cars. Typically a jump from circa 30v to seventy something. So 
now you have enough voltage to runa a brushless DC motor fo smallish size 
and heft, with about ten horespower and good efficiency (about 90%). Now, 
run the alternator at highway cruise and full braking, and you might 
store enough power to run a supercharger for maybe a minute at boost, 
maybe even more.  Never mind that a good brushless DC can run $5000 to 
$10000 US.  So you can do it with a cheapo bosch alternator, and some 
decent batteries.

Or you can buy a turbo, like I have.

Seth Allen