Originally Posted by vanttila

Directed at the OP, who said he knows "nothing" on the topic: From a quick googling I found that most dynohubs today draw 3 watts. If the OP pedals at 80 watts avg. during his summer trip, that's a bit under 4% of his power that goes into the light. That's not major, but worth noting. In addition, dynohubs weigh 1lbs and up, though the weight is at the center of the wheel, which lessens the power wasted in this (the rotational energy for a heavy wheel is higher, and it's all wasted when breaking...