A phantom load is something that uses power when it's not in use.  By using a plug meter, we measured the phantom load from this microwave to be 6.4 watts. To convert to a monthly load:

6.4(24 hours/day)(30 days/month) = 4.6 kWh/month.

To eliminate the phantom load, we used a power strip, and we turn the power strip off when the device is not in use. Notice that the clock on this microwave is not on. To heat food, we simply flip the power strip on, use the microwave, and then flip the power strip off.

By eliminating this phantom load we are saving 4.6 kilowatt hours per month of electricity, and this means that 4.6 lbs of coal per month does not have to be burned to provide standby power.

Many household appliances have a phantom load. Most transformers use between 3 and 10 watts while plugged in. Using a power strip with computers, entertainment systems, and microwave ovens eliminates phantom loads when not in use.