The two most popular methods to cool a commercial or industrial space like a warehouse, office, or retail store are fans and air conditioning (AC) units. While AC units are relatively new, fans have been cooling people off for centuries.
Fans are a straightforward mechanism. They can be as simple as a piece of paper you hold in your hand or as complicated as the spinning blades hanging from the ceiling. The basic premise, however, is the same: the circulation of air, which increases the rate of evaporation off your skin to make you feel cooler. Air conditioning units are far more complicated, but instead of increasing evaporation, they cool the air itself.
In mid-July of 1902, a man named Willis Carrier created the first real air conditioning system. It was in response to Buffalo, New York’s air quality problem, and it led to the ice-cold air we can have blowing through our homes and offices on the hottest days of summer. For the next few years, Willis tinkered with his idea, and in 1906 he was granted his first air conditioning-related patent. Soon, he figured out that controlling the relative humidity, absolute humidity, and dew-point temperature was a sure-fire way to condition air.
Although an air conditioner may seem simple, that’s far from the case. Essentially, an air conditioner consists of four main parts: a compressor, a condenser coil, an expansion valve, and an evaporator coil.
Refrigerant enters the compressor as a cool, low-pressure gas and leaves as a hot, high-pressure gas. Hot gas enters the condenser coil and condenses into a warm liquid as heat transfers into cooler air blowing over the coil. Warm liquid enters the expansion valve and expands into a cold, low-pressure gas/liquid mixture. The mixture enters the evaporator coil and evaporates into a cool gas as heat is absorbed from hot air blowing over the coil. This absorption of heat cools the air to a comfortable indoor temperature. Cool gas then re-enters the compressor and the cycle repeats.
Most businesses and homes around the world have air conditioning units or fans (or both) for keeping people cool and comfortable. Both fans and AC units have pros and cons — affordability, cost of operation, and how well they work being the most important — but if you properly manage whichever option you choose, you can be sure that your air conditioning needs are met.
Fans, of course, are more affordable than an air conditioning unit, but they don’t cool the air. Instead, a fan simply moves air around a room to create a gentle breeze that makes a person feel cooler. Think of it like this: a fan cools the body of a person in a room, while an air conditioning unit cools the air in the room.
A lot of different variables go into considering the cost of running an air conditioner vs a fan. Clearly, a ceiling fan is the less expensive option of the two, but even those can have a large price disparity. Both alternating current (AC) and direct current (DC) fans have the main function of increasing airflow. AC fans run directly from the power supply in your building while DC fans use electronics to convert AC power to DC power. While AC fans are generally more affordable to purchase, they typically use more overall power than DC fans. Some estimates, in fact, say that DC fans use up to two-thirds less energy than comparable AC fans. DC fans, on the other hand, are a little pricier to purchase initially, but will save you money in operating costs in the long run.
Air conditioning, however, can cost quite a bit more money, but when it comes to cooling air in a building, they are far superior. They also use far more energy. Similar to AC and DC fans, air conditioners offer different options at different price points, but they too have positives and negatives. Smart air conditioning, which is basically the integration of Wi-Fi into AC units, allows you to control your AC through your smartphone. More advanced smart air conditioning units enable the user to schedule when their AC unit turns on or off, set temperature and humidity triggers, track usage history, and control features that depend on your location. While smart air conditioning systems certainly make it easier for the user, they do come at a cost — but, like DC fans, they can drastically decrease energy usage.
When it comes to maintaining cool temperatures in commercial or industrial spaces like warehouses or auditoriums, for example, air conditioning units are far superior to fans. Fans can only move the air that's already in the building. The circulation cools your body, but not the air itself. When it is extra hot outside, fans can provide a cooling breeze, but a fan cannot introduce cooler air to lower the temperature inside a building.
Air conditioning units can lower the actual temperature in a space relatively quickly by introducing cool air. They also have the added benefits of humidity control and air filtration, which can remove particulates.
When it comes to installation, fans are much easier. Portable fans can be moved around a building according to need. Installing an air conditioning unit can be labor intensive, and generally requires a professional installer. Fans don’t require much, if any, maintenance. Air conditioning units need to be regularly maintained to ensure proper functionality. In general, air conditioners also must be incorporated into the design of a building. Central air conditioning requires ducts and vents throughout the space, and ductless air conditioners can require minor renovations to install. Air conditioners also have refrigerants in them — especially the older ones —which can be harmful to the environment.
Another benefit of fans is that they emit less pollutants than air conditioners. Unless you take into account the emissions produced in creating the energy it takes to run one, they emit none.
For the most effective way of cooling a space, using an air conditioning unit in conjunction with a fan is your best option. The cooling effect of the fan enables you to set your air conditioning unit at a higher temperature than you might have to otherwise.
To sum things up, if your goal is to cool the air in a building and maintain a consistent temperature, an air conditioner is the superior option. However, they are generally more expensive than fans and require more complex installation and maintenance. Fans move air throughout a space, which cools your body by increasing the rate of evaporation. If your goal is to simply increase air circulation and personal comfort without breaking the bank, a fan may be the better option.