[taxcontrol]

746 watts = 1 horsepower

300W is then .4 Hp
A 300 hp truck would then need 750 of these systems
A 150 hp van / car would need 375 of these systems

That might get a tad expensive.

[AnalogReigns]

I guess with your calculations, since their van has 1/7 the HP as a push-lawnmower, it can barely move.

Better tell that to the driver cruising normally around Japan.