I run an E3 Supernova front light and a matching 3 LED rear. They are a 6V ebike specific light set that plugs in inside the motor housing and runs right off the display unit light button. During the winter months I run the light almost all the time during my almost 4 hour per day commute, and battery consumption is unnoticeable relative to the motor. Cold weather has a far more noticeable effect on the battery than the light.