While that would be less efficient than a traditional turbo, it would have the advantage of being able to provide full boost almost immediately at any engine speed. An electric centrifugal supercharger may well be more efficient than a directly driven positive displacement blower, with some performance advantages too. Any such device will require far more power than a standard alternator supplies, however.
"Rockets are just another name for trouble. Either you just had trouble, you are having trouble, or you are going to have trouble." - Milt Rosen, Viking Program Director, White Sands Missile Test Range
