Energy Guide for a 12000 BTU Air Conditioner

Room Size

• British Thermal Units (BTUs) are used to measure the cooling capacity of an air conditioner. Cooling capacity is most useful when trying to determine what size air conditioner to use in your home. According to the California Energy Commission, a 12,000 BTU air conditioner is ideal for cooling a 450- to 550-square-foot area. Cooling a larger room in your home with a 12,000 BTU air conditioner would be inefficient. You need either a larger air conditioner or multiple units.

Energy Usage

• Estimation of cooling capacity in BTUs is also useful when calculating the energy usage of a room air conditioner. When you purchase a new air conditioner, look for its EER (energy efficiency ratio) rating, which compares the voltage used by the air conditioner's power cord (either 120 volts or 240 volts in the U.S.) to its cooling capacity in BTUs. The higher an air conditioner's EER rating, the better, so choose an air conditioner with a high cooling output and a high EER rating.

Efficiency

• Look for the wattage value on your 12,000 BTU air conditioner, printed or etched near the product's nameplate. This value describes the amount of electricity the air conditioner uses in one hour on its maximum power setting. Divide this number by 1,000 to convert watts to kilowatts and estimate as accurately as you can the number of hours that you plan on using the air conditioner. Multiplying these two values together will yield an estimation of the electricity that your air conditioner will use in a day, a week, a month or any other time period you choose. To convert this estimation into dollar amounts, multiply the wattage value by the price per kilowatt hour that your utility company charges, printed somewhere on your utility bill.

Other Considerations

• Like all appliances, energy and cost efficiency are affected by how well the air conditioner is maintained. Failing to regularly clean your air conditioner's air filter will greatly reduce its energy efficiency. During the hottest times of the year, you can improve energy efficiency by keeping the air conditioner's thermostat set as high as is possible to maintain a comfortable temperature inside the home and by using natural ventilation such as ceiling fans, box fans and open windows.