Bicycles have been all over the news recently, with many cities adopting pro-bicycle policies to try and curb car usage. Also, many younger people are switching to bicycles, as it’s both a cheaper and hipper way to get around.

Many bicycles have lights for nighttime visibility—and though they use batteries, they shouldn’t be discouraged: Your personal safety is more important than the environment. But now there’s a way to be both environmentally sound as well as able to see at night: a battery-free bike light. The company Goodbye Batteries has created a light that receives its energy from magnets attached to the spokes of your bike. A pretty nifty invention, and surely a way to avoid looking like a hypocrite when someone points out your “battery-draining lights.”