For residential customers, many utilities provide a major incentive by offering discounts to those who allow the utility to control customers' air conditioners during periods of higher demand.
Residential customers can also save themselves money by improving air conditioning efficiency.
Buying a unit. Buying too large a unit is not only expensive, it can increase discomfort by not removing enough humidity from the air, leaving you feeling cold and clammy. Determine the size of the area to be cooled, making sure to close off unused rooms or areas where cooling isn't necessary. As a rule of thumb, an air conditioner should have 15 - 20 Btus for each square foot of living space to be cooled. Keep in mind, however, that this formula can be affected by a number of factors, such as the amount of shade around your house, amount of insulation, or size of your family.