Electric chains saws are quite efficient devices when compared to conventional, gas-burning chain saws. Some advantages are: they are easy to start and stop, run quieter, and there are no fumes to inhale, fuel to add or spark plugs to maintain. They also tend to be two or more pounds lighter on average. Electric chain saws do have some drawbacks though: most notably, they are tethered to an electrical cord, so your working area is limited. They also tend to cut wood slower, and are not as suitable for felling large trees.
Here are some electric chain saw retailers: Husqvarna Forest and Garden, Jonsered, Remington, Stihl.
Story via Mother Eath News