Page 14 - 2021 Parade Style Magazine

THE MORE YOU KNOW...
Understanding
the 20 Degree
Differential
Can lower energy bills & protect AC systems
During the summer, when the temperature can reach 100 degrees outside, consumers may wonder, “How did my energy bill go up when I haven’t changed my ther- mostat?” The answer is simple, and yet complex. Even though a thermostat’s setting may remain unchanged during summer months, the weather outside has changed. Still, some may ask how their bill can be af- fected when thermostat setting has not been changed to make it colder inside. It’s on the same setting.
This is where it gets a little more complicated. Air conditioning systems are not designed for extreme heat. They are made to cool indoor air to about 20 degrees lower than it is outdoors. CPS Energy calls this the “20-degree differential.” Assume a thermostat is set to 76 degrees. When outdoor temperatures average about 92 to 95 degrees, a well-maintained AC system works efficiently. Now consider that the summer months in central Texas can often bring intense heat. Except for two days, each day during July of 2020 was 97 degrees or higher, with one day reaching as high
as 107. Nearly half the month recorded triple degree weather, and during August of 2020 San Antonio saw nearly 30 days of intense heat.
Now let’s suppose it’s 101 degrees outside, and the thermostat is still set on 76 degrees. That’s a difference of 25 degrees, even before factoring in the heat index – which often means there’s more humidity in the air, causing an air conditioner work harder.
It is easy for consumers to learn how their individual AC system reacts to cooling their home on hot summer days with a simple experiment. Before 10 a.m., make a note of the thermostat setting and begin logging when the AC system comes on and how long it runs before
cycling off. Continue to log the cycle at the start of each hour throughout the day. As the outside
temperature in-
creases, the system
will stay on longer, and the rest periods between cycles will be much shorter.
Why is the compressor working so hard? Part of the air conditioning process involves the system taking the hot air from your home and sending it out- side. As it does that, there’s a heat exchange that happens. The exchange works best when the outside air being exchanged is cooler than the air being released. Once outdoor temperatures approach or exceed 100 degrees, the air exchange is not as efficient. This helps explain why so many AC systems break down in the heat of summer when they are needed most – it is a combination of the weather, your thermostat setting, and the simple mechanics of how the system works. Poor AC system maintenance increases the risk.
By understanding the 20-degree differential and taking some simple steps, consum- ers can better manage their bills and help protect their AC units.
How you can
Manage Your Bill
» Use fans in your home to help you feel 4-6 degrees cooler
» Set your thermostat between 78-80 degrees
» Raise your thermostat by 2-3 degrees when you are not at home
» Close your curtains and blinds when practical during the day
» Check and/or replace your air filters every 2 weeks from May through October
» Install solar screens to limit heat from sunlight entering the home
» Check ducts for air leaks
» Have your system inspected by a licensed professional twice a year in the spring & fall
» When buying an AC unit, look for one with a rating of 15 SEER or higher
14 || 2021 PARADE STYLE MAGAZINE
Remember that air conditioning a home can account for half of your energy bill!
For all-season tips for saving energy, visit cpsenergy.com/tips