Dragging a cord around isn't really an issue with some planning. The maximum length needs to be the maximum distance from your outlet.

The trick is always working your way away from your power source. I tried mowing forward and backwards, but rotary blades just don't cut very well backwards and feet can get cut off on grades.

Up and back working away from the cord; always turning away from the cord. The electric mower is very quiet with no exhaust or gasoline to breath. I don't add any fluids and has virtually no maintenance.