Lighting my way: hub-powered bike lights

As you know if you’ve read this blog recently, I spend an awful lot of time these days biking in the dark. Though the days are getting slooooooowly longer and the percentage of sunny vs. rainy days might be getting better, I, like many people here, still bike to work and home from work in the dark.


Mt Hood sunrise from Springwater(this is back when the sun used to rise as I was biking;)

In past years, that has meant that I had to very carefully monitor my bike light battery life. Because it’s basically immoral to buy and throw away as many disposable batteries as winter biking requires, James and I long ago opted for rechargeables — but those require a fair amount of logistical foresight. The worst thing ever is to leave your dark house in the morning and realize that in the process of taking off all your rain-wet clothes and dealing with your evening routine the night before you forgot to charge your dead batteries overnight. Or that you charged the AAA batteries that your back light uses but didn’t have time to charge the AAs for your front light.

But this year! For my birthday back in July, a friend of mine gave me a dynamo light: a light that runs on the power that I create simply by virtue of riding my bike. It looks like this (the black thing attached to my rack)


front dynamo bike light

…where the wire leads down to a generator hub on my front wheel. I plug it in there, and the energy created by my wheel turning somehow magically powers the light. (Okay, it’s not magic, but I don’t really know how the mechanics of it work. I imagine it has to do with friction.)


dynamo system(the whole system)

dynamo hub(and a close-up of the hub. My light plugs in right there on the left)

The best thing is that the hub on my front wheel creates enough power that I can also run another wire all the way to the back of my bike where it powers my rear light as well.


rear dynamo light(though this picture of it makes me realize my bike is really dirty;)

It’s awesome. Now, I never have to worry about batteries, since as long as I’m pedaling my bike, I’m creating enough power to leave my lights on. In fact, it’s a crazy amount of power: sometimes I feel like I have a mini floodlight on the front of my bicycle, which is pretty rad on the Springwater trail where there are no lights otherwise.

I would probably never have bought this sort of lighting system for myself, since the lights alone (when bought new, anyway) are fairly expensive, then the wheel with a generator hub like this could easily be another $150. Definitely enough that I wouldn’t have done it for myself, even though now that I have it I can’t imagine ever going back.

(Can we just take a minute and appreciate all the people in the world who start you down the path toward what you totally need in your life without knowing it? Thanks, David!:)

So these days, I just hop on my bike, flick the switch, and bam! I can see! No charging or batteries required. And since both lights are bolted on to my bike I don’t worry about them being stolen either, though of course they still could be like anything on my bike I suppose, given enough time and craftiness. I feel pretty invincible these days when it comes to lights, and pretty psyched that I can be the power that makes them shine.




  1. Good for you and your friend, and fewer batteries that need recycling, too. And of course, a safer journey!

    • Yeah. It always killed my soul a little to have SO MANY batteries that I couldn’t even throw away in the trash because of their toxicness. Much better with rechargeables, and EVEN BETTER this way:)

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