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Has your business switched to a programmable thermostat yet?

If the answer is no, you are very likely missing out on one of the easiest ways to lower your annual energy expenses.

According to the U.S. Department of Energy, simply turning down your thermostat by 7º -10º for an 8-hour period can save your business as much as 10% a year in energy costs.¹

Now, before you go thinking that you will either freeze or roast your customers and employees by adjusting your thermostat by 10º, first consider that these temperatures will only be experienced by empty desks, idle office equipment and anything else on hand while your business is closed.

You see, by installing a programmable thermostat to automatically adjust the temperature according to a preset schedule, no one — other than maybe the fish in the office aquarium — will ever notice a thing.

Thermostats 101

One of the most common misconceptions about thermostats is that they somehow make a heating system work harder than normal in order to bring a room back to a comfortable temperature.

First, a thermostat is really nothing more than a fancy on/off switch.

When the internal thermometer inside the thermostat measures a temperature that is below its set minimum, the unit sends an electronic signal to the furnace telling it to turn on and start sending heat — in the form of either hot air or hot water — to the specific area (or zone) in the building that the thermostat is located.

As soon as the temperature in that part of the building reaches a certain point, the thermostat sends another signal to the furnace to turn off. It's as simple as that.

Thermostats don't control the temperature of the water or air a furnace produces. Rather, thermostats control how long a heating system produces heat.

So, for example, if you were to set your thermostat to maintain a constant temperature of 70º and then open all the windows and doors to let in cooler 55º outside air, your heating system will still only produce as much heat as it is designed (and set) for. No more, no less.

Unfortunately for business owners, the reality is that the furnace has no idea that the windows are open and will continue to run and run and run and run… trying desperately, yet never actually reaching the 70º mark.

Lower Temps = Lower Bills

So, with this in mind, you can see that a thermostat set to a lower temperature will end up sending fewer signals instructing the furnace to send more heat through the system. And the less a furnace produces heat, the less energy it consumes… and the lower your energy costs will be.

The same concept applies to cooling room temperatures as well.

Instead of an open window, think about how keeping the refrigerator door open forces its cooling system to constantly try and combat the warm air entering the space inside. The same principle applies with the same result: wasted energy and wasted money.

Next: Debunking the "Constant Temperature" Argument

Another misconception about the most efficient way to either heat or cool an area is based on the notion that maintaining an even temperature will require less energy than warming or cooling a space back to a comfortable level.

While on the surface this argument may appear valid, it does not factor in the relationship between air temperature and air pressure (called thermodynamics).

Often referred to as the "stack effect," the basic principle is that the natural movement of airflow within an enclosed space is controlled by air pressure…or, rather, the difference in air pressure, which is directly related to air temperature.

Who knew? Warm air doesn't rise.

We all learned in grade school that warm air rises. Unfortunately, this isn't exactly accurate. At the very least, it doesn't tell the whole story.

The truth is that warm air only appears to rise… when what is actually happening is that the colder the air temperature becomes, the more densely its molecules are packed together and the heavier it becomes.

This heavier, colder air essentially sinks and then forces the lighter, warmer air up to take its place. Additionally, the rate (speed) at which this happens is directly related to the differences in temperature. The larger the temperature difference, the stronger the force will be between warm and cool air.

The Force. Under pressure.

In layman's terms, the closer the temperature inside your building is to the temperature outside the building, the less pressure there will be to force the hot air out and pull the cold air in.

Basically, the cooler a building becomes, the slower it will lose its (heat) energy. This heat transfer is happening constantly, whether or not you are conditioning the space to be hotter or cooler — so by keeping the temperature low for a longer amount of time, you are essentially reducing the amount of energy (heat) that is lost in a 24-hour period.

Again, the same concept applies to keeping inside temperatures higher in the summer to save on cooling costs.

Programmable Means "Set It and Forget It"

The best thing about installing a programmable thermostat in your office is that once you've set it up based on how and when your building is normally occupied, you generally don't have to bother with it again.

While it may take a few tweaks to set the temperature at a point where everyone is comfortable, the real value comes from its ability to shut off the heating or A/C system when the building is empty — after hours and on weekends. Then, come Monday morning, the system will automatically bring the temperature back up (or down) before the first employee arrives back at work.

Incremental Savings Add Up Over Time

For a typical business, the energy savings that can result from properly managing the temperature of your building can be substantial — especially when you consider that a business typically occupied from 7:00 a.m. to 7:00 p.m. is still technically vacant during the remaining twelve hours each day.

Clearly, simply adjusting your thermostat to automatically lower the inside temperature by as little as 5º -10º during the 100+ hours a week that your business is not operating will dramatically lower your energy usage and result in noticeable savings at the end of the year.

For other ways to save costs and reduce energy usage, download PG&E's "25 Money Saving Tips for Businesses" eBook. This eBook will provide business owners with energy solutions that can lead to significant savings.

Referenced in article:

1. U.S. Department of Energy