Goathead
100 W
As used by the German post office, but with stats on adoption throughout Europe . . .
http://www.nytimes.com/2014/08/19/business/e-bike-sales-are-surging-in-europe.html?ref=business&_r=0
http://www.nytimes.com/2014/08/19/business/e-bike-sales-are-surging-in-europe.html?ref=business&_r=0