On hot and humid months, all homeowners, renters, and property managers tend to agree on one thing – saving money on the cooling bill is a good thing. One way that people have looked into trying to save money is by shading the outdoor portion of their central air conditioner. Keeping that part out of the sun's rays means that it won't get hot, which means your AC won't have to work as hard. This will save you money, right? Not necessarily. And that's due to how the compressor (the outside part of your AC) works.
The Ins and Outs of Your Compressor
Your central AC removes heat from your living spaces by sucking in the warm air and cooling it at the evaporators in your basement. Heat is transferred to the coolant, and the now warm fluid is pumped to the outdoor section. Ambient air reduces the coolant's temperature so it can then absorb more heat from your home.
Does Shading Do Anything?
The Florida Solar Energy Center conducted a study on this question in 1996. Their study showed that shading the compressor alone was ineffective in reducing the amount of energy that was used. They used three separate locations and measured the reduction in wattage used by each unit when shaded. In one case, because of the intermixing of the hot exhaust with the intake air, the AC used more energy. Where there was a reduction of energy used, the savings was only 3%, barely enough to cover the cost of constructing the shading trellis.
Why Do People Say to Do It?
When people recommend shading your air compressor, they are often citing a study by the US Department of Energy. This study recommends using landscaping as a method of saving energy on your heating and cooling costs, with savings ranging between 10 and 25 percent off total costs. It's important to note, however, that these methods also shade the whole home from both solar energy and wind, not just the compressor. This shading reduces the amount of heat gained in the summer and lost in the winter, making the overall HVAC system work less year-round.
While shading your compressor alone may give you some small savings, it's often a break-even venture. To maximize your savings, investing in an energy efficient landscaping scheme will give you the best return on investment. With strategic placement of trees to shade not only the compressor, but also your home, you can save significant amounts over the years.
For more information, talk to a professional like One Hour Heating & Air Conditioning.