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Myth Busters

There are a lot of myths about energy efficiency and energy conservation floating around. Below we debunk several of the most common ones.

Myth #1 - Turning lights off and on uses as much or more energy than it saves.

Depending on the frequency of switching, this may have been true 15 or 20 years ago, but not today. Older florescent fixtures contained magnetic ballasts that required energy to warm up and fire up the florescent tubes. However, today's electronic ballasts operate very differently and require a small fraction of the power the magnetic ones did. The savings from turning off the lights far out-weighs the negligible amount of energy used to start the lamps. 

Myth #2 - Turning lights off and on shortens the life of the bulb.

Technically, this may be true; however, bulb life is not the real issue. The real issue is how soon you have to replace the bulb. A light that is left on 24/7 will have a longer burn time than one that is turned off when not needed. But, because the light is being turned off, the burn time is spread out over a longer period. Which means that the replacement time is greatly extended.

Myth #3 - In the larger scheme of energy conservation, one person can't make that much of a difference.

As with many other myths, this one has some truth to it. If you look at how much you can save as one individual in your office or classroom, it may not add up to one dollar per day. However, if every one also did that little amount, by time you multiply it by the total number of employees, or number of offices/classrooms, and by the number of operating days in a year, you will be easily into the tens of thousands of dollars saved annually.

Myth #4 - If saving energy was going to produce that much revenue, then everyone would already be doing it.

While there is a natural resistance to change the reality is that the most successful companies and organizations are promoting and practicing energy conservation. For a company focused on profits energy is an expense. Therefore if the company typically earns a 10% profit margin, every dollar save on energy is like making $10 in new sales. For public and municipal organizations there is a saying: "Every dollar saved is a piece of some ones salary." Reducing the amount spent on energy reducing the need to raise taxes or cut spending in other areas.

Myth #5 - Energy conservation means I'm going to be uncomfortable.

Many people have the idea that energy conservation means going without. They're going to be cold in the winter, hot in the summer, and have to squint to read in a dimly-lit office or classroom. Unfortunately, this belief has been reinforced by experience over the years in ill-conceived practices to reduce energy costs. However, a more thoughtful approach focuses on reducing energy waste. Industry experts estimate that as much as 10-15% of energy used in a facility is wasted. A good energy management plan focuses on optimizing energy use when it is needed and eliminating wasteful practices. This can be done through retrofitting to better technology and operating the systems more effectively. There is a lot to be saved just by reducing waste behind the scenes without having to make people uncomfortable. 

Myth #6 - Turning computers off and on shortens the life of the computer.

When you think about it, the "life of a computer" has nothing to do with how long it will operate. It has to do with when it becomes obsolete. How many old computers do you see that still work, but nobody will use them because they don't run the programs we need them to run. What if switching the computer on and off will reduce the operational life of a computer from 12 years to 10 years? How many people are even able to use a computer today that is 10 years old? The answer to Myth #2 applies here as well. Turning off computers at the end of the day vs. leaving them on 24/7 will actually extend the time when replacement will be operationally required (10 years of "on" time spread out over 15 years or more).


Myth #7 - The lower you set the thermostat the faster it will cool. Or, the higher you set the thermostat the faster it will heat.

In spite of this popular practice, heating and air-conditioning (HVAC) equipment works at the same rate regardless of the setting. All it sees is "on." The problem with this practice is that over-cooling or over-heating will occur until the extreme temperature setting is satisfied. The best practice is to set it at the desired temperature for the space and activity. It will cool down or heat up just as fast as if you set it to the extremes, relieving you of the need to readjust later.

Myth #8 - You can dehumidify a room by turning down the air-conditioning to 60 degrees.

Unfortunately this is not true. Over cooling a space simply makes it cold and damp. In order to dehumidify air it must be cooled (to about 55F) and then reheated either by heating equipment or by heat generated in the space (computer, lights, office equipment, people, etc.). Over cooling a room to 60F will simply make the moisture in the air will be deposited as condensation on your office equipment, walls, windows, and anywhere else in the room that has reached the dew point. This sometimes happens in hot and humid climates where wet carpet cleaning is occurring. The water from the cleaning evaporates into the air increasing the humidity in the room. If the room temperature is set above the dew point of the air in the room (usually 72 degrees or higher), then the condensation will occur in the HVAC equipment and drain to the outdoors. Otherwise, it occurs on the walls, computers, desks, etc., leaving a huge mess and potential for microbial growth.


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