Commercial HVAC systems can be very expensive to run. Since you are heating and cooling much larger areas, you need to use bigger appliances that consume more electricity and fuel. Of course, this is largely unavoidable. But, this is not to say that there aren't a few ways that you can make your commercial HVAC system more energy efficient.
Ducting is Key
The set up and design of your ducting has a big influence on how efficient your HVAC system is. For example, even if you have a brand new, super efficient furnace, a lot of this heat could be lost if your air ducts are not airtight. Obviously, most air ducts will remain airtight unless they are moved or hit in anyway. On the other hand, most commercial buildings don't have insulation around the ducting (whether it is within the walls or exposed). This is a particularly important issue if you have exposed ducting.
Exposed ducting is popular because it makes the building construction much cheaper. It is also currently very trendy in modern interior design. Exposed ducts are particularly popular in commercial construction. You will often see it at large stores, where houses, and modern design spaces. With all of the ducting, pipes, and wiring visible, most building owners have them painted a solid color, but they almost never have their actual ducts insulated.
Ducts Inside Your Walls
When the ducts are inside the walls, encapsulated by the drywall or metal, it isn't as important to have the actual ducts insulated. The wall will provide some vital insulation. Of course, it costs more to construct a building that has the HVAC encapsulated inside the walls. But, it might be worth it if you have a large building in a cold climate. For instance, a cold warehouse in a winter climate like New York's can cause exposed ducts to lose a lot of heat.
But, whenever there is a visible duct, it will benefit if you add insulation to it. So, if you do want to have expose ducting, you either need to be willing to add insulation to it, or you need to use more electricity in order to heat and cool your space. As you can see, commercial buildings require special considerations when it comes to energy efficiency, insulation, and HVAC maintenance. Spending a little extra money now will alternately save you money on a monthly basis.