This week's offering is being written as we cruise at an airspeed in excess of 600 miles per hour well above the clouds at an altitude of about 37,000 feet. We are on our way to New York City for a whirlwind three-day business trip, and yes, we're in an airplane.

Before we left San Francisco we promised our editor at the AP that we would have our column on his desk by the time we arrived in New York. We knew that our full schedule would prevent us from writing the column while there. So a column conceived in flight became our only option. Bottom line: It is necessary for us to write the column on the plane. It will be filed on time and it won't interfere with our busy schedule in New York. A portable computer with word-processing software makes it possible, and a battery makes the computer operable. Batteries are the special little devices that power a pacemaker, a camera flash and your TV remote-control unit.

Duracell, Energizer, Panasonic and Rayovac have offered a new breed of alkaline batteries that should last 30 percent to 60 percent longer than current models. (The percentage of increased power or lasting quality varies according to which manufacturer you listen to.) We understand that the biggest difference will be when these new alkalines are used in new high-tech devices that require quick surges of power. The word is that the new offerings will be available at about the same price.

The same appliance made by different manufacturers can drain a battery at a different rate. One brand of appliance for example might use less power to fire up a CD (or a radio or a cassette, etc.) than another brand. Therefore, some batteries last longer in some brands of appliances than others. However, tests by Consumer Reports magazine showed that a single toy - operating continuously - ran for almost identical lengths of time with a variety of brands of batteries. The magazine said that test differences were so insignificant that batteries should be purchased by price rather than brand.

You might not be aware of it, but alkaline batteries no longer contain mercury, making them safe for landfills. However, not all batteries are safe to discard. Be sure to read the manufacturer's disposal warnings carefully.

Alkaline batteries also store well. They can last "on the shelf" for as long as five years. This means that purchasing several when they are on sale makes good sense. We use leftover rundowns from our kids' toys to operate remote control units and other low-drain devices. You would be amazed how long you can use a battery in a given device, even when it no longer has sufficient power to run another.

If you use a lot of batteries, consider the alkaline rechargeable type. The batteries themselves cost a little more, and you must also spend a little extra to buy a charger, but, in the long run, recharging is a lot less expensive. Where nickel-cadmium might fit your recharging bill, keep in mind that they are not landfill friendly.