Energy Saving Tips: Air Conditioning

• Air conditioning can account for up to 50 % of your summer electricity bill so try to use it only when necessary to remain comfortable.
• Average residential daily energy consumption is 25 KWh or about 1 KWh per hour.
• A room air conditioner adds about 1 KWh per hour to your energy usage. If it is left running for 24 hours, that will total about 24 KWh, doubling the average residential energy consumption. The cost to run a room air conditioner for 24 hours will average between $2.00 - $3.00 a day. (A ceiling fan will cost about 15 cents a day. A portable fan about 30 cents.)
• When shopping for a central or window air conditioning unit, choose newer Energy Star(r) qualified models which are up to 70 % more efficient than older models.
• A central air conditioner adds about 3.5 kWh per hour to your energy consumption. If your central air conditioning unit runs for 24 hours, it will consume about 85 KWh, more than tripling average residential daily energy consumption. The cost to run a central air conditioning unit for 24 hours will average $8.00 - $12.00 a day.
• Keep air conditioning thermostats set at 25° or higher. You will use 3 to 5 per cent more energy for each degree your air conditioner is set below 24° C (75° F), so set the thermostat at 25° C (77° F) to provide the most comfort at the least cost. The less difference between the indoor and outdoor temperatures, the lower your overall cooling bill will be.
• Don't set your thermostat at a colder setting than normal when you first turn on your air conditioner. It will not cool your home any faster and could result in excessive cooling and unnecessary expense.
• Don't place lamps or TV sets near your thermostat. The thermostat senses heat from these appliances, which can cause the air conditioner to run longer than necessary.
• Turn off lights during the day and keep blinds drawn so you can keep air conditioning use to a minimum. This is especially important for windows or doors that get direct sunlight.
• Turn off air conditioning at night and open windows.
• If you use a ceiling fan or tabletop fan in conjunction with air conditioning the "wind chill" effect means you can set your air conditioner higher to 26° or 27° C (79° to 80° F) and still be comfortable. Every increase of 1.7° C (2° F) on your thermostat can result in a reduction of 15% in air conditioning energy use and can result in a significant savings on your summer electric bill.
• Ceiling fans cost about 1 cent for 2 hours of operation. Make sure your fan is blowing air downwards in the summer.
• A portable fan costs about 1 cent per hour.
• Whole-house fans help cool your home by pulling cool air through the house and exhausting warm air through the attic. They are effective when operated at night and when the outside air is cooler than the inside air.
• Leave your furnace fan on continuously to circulate cooler air from the basement up to other floors. Some furnaces have a way of opening a duct to draw even more cooler basement air into the system.
• Plant trees or shrubs to shade air conditioning units, but not to block the airflow. A unit operating in the shade uses as much as 10% less electricity than the same one operating in the sun.
• Try to put your window air conditioner in a window that faces north or is shaded. If you keep the air conditioner out of direct sunlight its efficiency will improve; an air conditioner that is exposed to direct sunlight will consume 5% more energy than one that is shaded.
• Consider closing off the dampers of your basement ducts. This will send more cooled air upstairs. You can reopen them in the fall to allow heated air to be sent into the basement.
• If you have a fireplace, keep the damper tightly closed when not in use. A glass fire screen can help minimize the loss of conditioned air.
• Be sure you check your air conditioning filter at least once a month and clean or replace if dirty.
• For energy savings, set the fan switch on a central air system or room air conditioner on "automatic" instead of "on" or "continuous."
• Keep doors and windows closed when the air conditioning is on. Teach children to close doors when they go in and out.
• Use programmable thermostats
• Turn off pilot lights on gas fireplaces during the summer months

• The outside unit may become clogged with leaves, grass clippings and other debris. If the outside unit is located under or next to a dryer exhaust vent, the lint exhausted may collect in and around the coils and cause the air conditioner to run less efficiently and thus require cleaning more often.
• To clean the outside unit, first ensure that the power is turned off at the service panel. Then following the manufacturer's instructions, gently clean out the debris that has collected.
• Use your electric meter as a diagnostic tool. Monitoring your electricity consumption will help you notice any unusual rise in consumption that may be caused by an air conditioner or heat pump operating low on refrigerant.

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