There's nothing better than a chain saw for those big wood-cutting jobs. Unfortunately, the fuel, which is often an oil-and-gas mixture, can be quite the pollutant, with many chain saw emissions so powerful they even break some state pollution emission laws.
One greener alternative is the electric chain saw. Unlike a fuel-powered chain saw, you can use an electric saw indoors since it doesn't produce any fumes. An electric chain saw also tends to be lighter and less noisy, and you don't have to worry about running out of gas before the task is completed.
Another alternative is a rechargeable chain saw. You can now find chain saws with an 18-volt lithium-ion battery or interchangeable nickel-cadmium batteries. These offer a convenient cordless design, and they're lighter and less noisy than gas chain saws. A number of today's rechargeable chain saw designs offer sufficient cutting power for most jobs.