The electric revolution has hit scooters, as the battery-powered versions are hitting urban areas across America. It seems like a good thing for the environment at first glance, but the real story may be more complicated.

We don’t yet have any data from the scooter companies themselves, but E&E News [paywalled] discussed some of the factors that would affect the environmental footprint:

• Replacement trips: e-scooters are an environmental win if they’re replacing what would otherwise be an automobile trip. But if they’re replacing a transit ride, it’s usually more efficient to ride in a bus or train than take a single e-scooter ride.
• Electricity source: if the energy to produce the electricity for the scooter’s battery comes from coal, these rides may not be so clean after all.
• Charging process energy: the e-scooter companies pay people to collect the scooters at the end of each day, to bring them somewhere to charge. If those individuals are driving around in fossil fuel-powered cars with excessive miles traveled, those emissions could significantly offset (or even swamp) the e-scooter benefits.
• Disposal: at the end of their useful life, how are the e-scooters disposed? There will be an emissions footprint to disposing or recycling them, as well as a potential toxicity issue.

So while e-scooters certainly hold a lot of promise for reducing emissions, without more data — and potentially some policies to ensure positive environmental outcomes — we don’t yet know for sure if that’s the case.