Most lawn mowers are powered by gasoline. Up until recently they have been the easiest mowers to use. It was necessary only to pull the starter cord a few times, or use the electric starter, and then mow to your heart's content. But gasoline-powered mowers are noisy and they do rather pollute the air with their emissions.

One of the knocks against the electric-powered lawnmower was that it was awkward to use. The mower must be plugged in via a long power cord, and care must be taken not to snarl or run over the power cord.

Now, you've got another choice - the battery-operated lawnmower. A battery-operated lawnmower will generally have enough power to allow the operator to mow both the front and back yards on one charge, unless they are extremely large.

It all depends on the battery, though. Some batteries last for thirty minutes between charges, others last up to an hour. The key thing is that they are rechargeable, so that there's no need to bury them in a garbage dump. Although...even these batteries only last about five years or so - and then must be recycled.

There are several types of batteries: alkaline - which are not used in lawn mowers, lead acid - which are gradually being replaced by nickel cadmium, and lithium batteries - which are not only expensive but also have low storage capacity.

Nickel cadmium batteries

If you are buying a new battery operated lawn mower, make sure you get one powered by a nickel cadmium (Ni-cad) battery. They are simply better than the lead acid - they can be recycled and are environmentally friendly.

Extending battery life

As with any other type of mower, there are times when you should mow your lawn and times when you shouldn't. You should never try to mow wet grass - it produces a tremendous strain on the battery - or engine - and doesn't do your grass much good, either. Don't let your grass grow such that you're cutting off more than three inches at a time - again, bad for the engine or battery, and bad for the grass itself.

Ni-Cad batteries

Ni-Cad batteries are maintenance free. All you need to do is make sure you do not re-charge the batteries until they are completely discharged. The batteries have a 'memory' - if you recharge them when they don't need to be, they will remember the energy state they were at when they were recharged, and will believe themselves to be run down the next time they reach that state - even though they have plenty of power left. (Okay, there's a bit of anthropomorphism there, but you get the idea.)

If you're concerned about the environment - and we all should be - the battery-operated or electrical lawn mowers should be our choice.