Originally Posted by noglider

I agree with the dynamo advice, as I've been using dynamos for a few years. You don't notice how much trouble goes into charging a headlight until you stop. Then you realize it's like banging your head against a wall. Taillights are easier to deal with since a bright taillight can run daily on a single charge for weeks.

However, dynamo lights aren't very bright. This isn't a problem for me. I seem to do OK with low intensity lights. I'm not sure what my lights put out but 300 lumens is my guess. I can ride comfortably at 12 or 15 mph at that speed. Whether this is good enough for you is something only you can say. Some people are not satisfied unless they have 1,000 lumens, and that sounds crazy to me, but to each their own. However I will point out that if your beam is not "shaped," then you need more lumens. And that is to say if it is shaped, you need fewer lumens. I like shaped beams of the German type. There is a sharp cutoff at the far edge of the beam, and most of the light goes to the far edge. I do not light up the trees or the road's shoulder, and the light does not shine in the eyes of pedestrians or motorists or cyclists. This is how I get away with a low-lumen light. I do not have exceptional night vision.

If you do want a high intensity light, you could get a super-high intensity light, say 2,000 lumens, and run it at half power so the battery lasts long.

Another solution is to use an external battery, and that requires a light that can run off an external source.