It is the middle of summer and many are seeking the coolest, shadiest places possible to stay cool outdoors.  But naturally, thoughts turn to air conditioning - one of the biggest energy users in homes across much of the country. Air conditioners use about 5% of all the electricity produced in the United States, at a cost of over $11 billion to homeowners. As a result, about 100 million tons of carbon dioxide are released into the air each year—an average of about two tons for each home with an air conditioner.

By switching to high-efficiency air conditioners and taking other actions to keep your home cool, you could reduce your energy use by 20% to 50%. In some states you may be able to get a rebate, tax break, or other financial incentive on a qualified energy-efficient ENERGY STAR air conditioner.  

Properly maintaining your air conditioner is key to keeping it running efficiently. The most important thing is to routinely replace or clean its filters. Keeping the filter clean can lower an A/C unit's energy consumption by 5% to 15%.


Also, check the evaporator coil every year and clean it if necessary. For outdoor A/C units, condenser coils can also become very dirty if the outdoor environment is dusty or if there is foliage nearby. Cleaning the area around the coil, removing any debris, and trimming foliage back at least two feet gives adequate air flow around the condenser. Also, shading the outside unit can increase its efficiency by up to 10%! 

For window units, inspect the seal between the air conditioner and the window frame to ensure it makes contact with the unit's metal case. Moisture can damage this seal, allowing cool air to escape from your house. When an A/C unit needs more than the regular maintenance routine, hire a professional service technician.

Another good way to save money on your cooling bill is to improve airflow in your home through various ventilation options, since fans use far less energy than A/C units. Adding a window fan or ceiling fan to your bedroom or installing an attic fan can reduce or eliminate the need to run an air conditioner at night. Ventilated attics are about 30°F cooler than unventilated ones. Properly sized and placed louvers and roof vents help prevent moisture buildup and overheating in your attic. Lastly, keep inside doors to bedrooms and bathrooms open for proper air circulation and ventilation. Oftentimes closed off rooms don’t get the air they need and impact the energy usage of the rest of the house.

Plant well-placed trees to shade your home.  This will save up to 25% on your energy costs and cool the surrounding air temperatures by as much as 9°F while also helping to remove some carbon from the atmosphere.  Position small groundcover plants to reduce radiant heating from the ground near the house; install awnings and overhangs to keep sunlight off windows, and keep your blinds and curtains closed during the day; and always ensure proper ventilation when using shade barriers to keep walls cool.

Have a great summer—keep saving energy and cutting emissions—and be cool!