Trying to “go green” is a pretty big endeavor. If you’re already riding your bike to and from your daily routine places, then you’re on the right track. However, if you have to ride at night, you need a bike light, and especially one that’s not going to need new batteries all the time. Having to toss batteries isn’t good for the environment, or your wallet.
The Blackburn Flea 2.0 USB Rechargeable Bike Light makes use of natural light to charge during the day to keep you safe at night. If you forget to charge it via sunlight, you can always use the USB dongle to charge it instead. The front light holds a charge for up to 5 hours with 4 extremely bright LEDs, while the rear provides up to 12 hours on one charge. This can come to you for about $30, and will prevent you from tearing through a pack of batteries every week or two.