This product is perfect for those who want to save energy while taking care of their lawn. Solar Powered Lawn Mowers are designed to use the sun's energy to power the motor, eliminating the need for gas or electricity. These mowers are easy to use and maintain, and provide a clean
From Wikipedia
A robotic lawn mower is an autonomous robot used to cut lawn grass. A typical robotic lawn mower requires the user to set up a border wire around the lawn that defines the area to be mowed. The robot uses this wire to locate the boundary of the area to be trimmed and in some cases to locate a recharging dock. Robotic mowers are capable of maintaining up to 100,000 m2 of grass.