Compact Fluorescent lamps use up to 75% less energy than standard incandescent lamps and last up to 10 times longer. Forconversion from Incandescent lamps to Compact Fluorescentlamps, start with the current wattage of your Incandescent lamp anddivide it by 4 to determine the wattage equivalent of the Compact Fluorescent lamp you will need. Choose a Compact Fluorescent lampwith the wattage nearest to that number.

You can use a 25 or 27 watt Compact Fluorescent and it will produce the same light output as a 100 watt Incandescent, while saving you 75 watts

The other factor you want to consider is lamp color or color temp. If you are replacing an Incandescent lamp with "Soft White" color then you would want to lookat a Compact Fluorescent with a color temp. of 2700-3500K. See chart below for color temp. guidance