The BTU an HR of Air Conditioning Required for Houses

Definition

• A single watt-hour of energy converts to 3.14 BTUs, according to the online Miser Products Sales Guide. For example, a toaster that consumes 10 watt-hours of energy gives off 31.4 BTUs/h of heat. To determine the amount of heat generated in your home, you would need to convert the wattage of all of your electrical appliances to BTUs/h and account for the effect of direct sunlight through your windows and walls. For central air conditioning units, the BTUs/h is given in a unit known as tons where one ton equals 12,000 BTUs/h.

Square Footage

• When determining the BTUs/h you will need from your air conditioner, you will need to measure the square footage of your outside walls, your windows, your roof, the total wattage of the electrical devices in your home and the square footage of your kitchen. Because the stove and oven generate heat in a confined kitchen, that can have an effect on your energy consumption. To get an accurate indication of the BTUs/h you will need for your air conditioning unit, you can apply all of your information to the air conditioning sizing worksheet found on the Consumer Reports website.

Considerations

• Some of the factors that affect energy consumption include the amount of shade from sunlight offered by trees surrounding your home, the number of people that regularly occupy the house, if you have thick curtains in your windows and how often those curtains are closed. Replacing older light bulbs with energy efficient florescent bulbs will also help to reduce the energy consumption in your home.

EER Rating

• The EER rating for an air conditioner is its Energy Efficiency Ratio as determined using standards created by the U.S. Department of Energy. The higher an air conditioning unit's EER ratio, the more energy efficient that unit is compared to other units of a similar size. Window air conditioners have an additional Energy Star feature that maximizes the efficiency of hot air transfer, according to the California Energy Commission Consumer Energy Center website.