ON the average, residential air conditioning accounts for close to 8% of the home's annual electrical consumption.
ENERGY STAR qualified central air conditioners have higher seasonal energy efficiency ratio (SEER) and energy efficiency ratio (EER) ratings, making them about 14% more efficient than standard models.
The central air conditioner also needs a blower motor – which is usually part of the furnace – to blow the cool air through the duct system. The only way to ensure that your new air conditioner performs at its rated efficiency is to replace your heating system at the same time. It’s especially recommended if your furnace is over 15 years old. If you purchase a new energy-efficient air conditioner but connect it to an older furnace and blower motor, your system will not perform to its rated efficiency.