Get Yourself An Energy-Saving Air Conditioner

May, 31 2013 16:05

Get Yourself An Energy-Saving Air Conditioner

With the hot summer weather fast approaching, a lot of people are looking to upgrade their window air conditioners.  And rightly so.  An old air conditioner can be an energy-draining appliance that will do the job minimally well and cost you maximum dollars on your next energy bill.  With air conditioning costing U.S. homeowners approximately $15 billion annually, now may be the time for you to consider a new, more efficient, machine.

What Size to Get?

When looking for a new air conditioner, there are two things to look for:  cooling capacity (measured in British Termal Units or BTUs) and the energy-efficiency ratio. 

There is a simple formula for calculating the correct BTU rating for a given space:

   (Square footage x 10) + 4000

So for a 300 square foot space, the BTU capacity should be no less than:

   (300 x 10) + 4000 = 7000 BTUs

How Energy Efficient Is It?

An air conditioner’s energy-efficiency ratio is the ratio of the cooling output divided by the power consumption.  The higher the energy-efficiency ratio, the more efficient the air conditioner. 

The U.S. Department of Energy requires that room air conditioners have an energy-efficiency ratio of 8.0 or more, depending on the type and capacity of the unit.  Air conditioners that have an energy efficiency ratio of 10 or more usually qualify for the federal government’s Energy Star label.  If the machine you’re looking at has an Energy Star label, it’s probably a good bet.

To give you an idea of how the energy efficiency ratio can impact you, here’s something to keep in mind: replacing an old unit with an energy-efficiency ratio of 5 with a new unit that has an energy efficiency ratio of 10 will lead to 50 percent energy cost savings to run your air conditioner.   

Central Air conditioning

Central air conditioning is more efficient than room A/C units, because they keep the whole house cool and do a better job at reducing household humidity levels than individual room units.  While this will lead to greater savings in a shorter time on your energy bill, central A/C is a pricey investment at $4000 for just the condenser and initial setup (plus any new duct work required to distribute the cool air throughout the home). Central A/C is a better option if you’re a homeowner who plans to stay in your home awhile.  Room A/C units, which only cost a few hundred dollars, are the preferred cooling method for renters or those who only need to keep one or two rooms cool.

Other Ways to Stay Cool

Without A/C (or to save on A/C costs), there are other things you can do to keep cool:  improve insulation, replace old appliances and light bulbs that generate lots of heat, and use fans, which are very energy efficient.  Using these suggestions can keep your temperature cool and keep your energy bills down.

Contact your local Building Energy Pros Affiliate to help improve your home's performance and save on your energy bills. Visit