Vista Window Film
Vista Window Film greenbldgs
Twitter - join the conversation


Commercial Window Films rss RSS email E-MAIL

Residential Window Films  rss RSS email E-MAIL

Improve HVAC Energy Efficiency Year-Round

December 16, 2014 | 4 comments

HVAC systems are used continuously in commercial buildings. In fact, HVAC systems account for roughly 41% of total commercial building electrical usage – almost double that of any other building system – according to Alliant Energy. (Air conditioning alone represents 45% of the total peak energy use.) This obviously increases monthly utility bills, but also presents a big opportunity for regular energy savings.

Here are a few ways to save as much HVAC energy as possible all year long:

Invest in Regular Maintenance
Small problems, like dirty condenser coils, can affect HVAC energy efficiency and increase operational costs. According to Alliant Energy, a 10-ton air-conditioning system that operates 1,500 hours per year may experience up to a 37% increase in operating costs and a 30% loss in cooling capacity when condenser coils aren’t cleaned regularly.

Filters present similar problems if they’re not replaced every three to four months. According to the National Renewable Energy Laboratory, clean filters may increase HVAC fan power (unless speed is controlled by a variable frequency drive). But dirty filters can reduce airflow and heat transfer, overworking the HVAC system. A maintenance plan may help you identify equipment problems early, possibly lengthen equipment life, and increase energy efficiency.

Also plan to regularly tighten belts (or switch to synchronous belts) to prevent slippage, which ultimately wastes energy.

Check for Blocked Vents
ENERGY STAR says that blocked vents may cause HVAC systems to use 25% more energy to distribute air. Occupants and tenants may not realize the impact of closing a vent or blocking it with furniture or a piece of paper when they’re too hot or too cold.

Periodic building walkthroughs will help pinpoint where this is happening. If you notice vents that have been tampered with, talk to tenants or occupants. Are they too hot? Too cold? Is the workspace too drafty? By identifying the problem, you’ll find a solution that doesn’t involve blocking vents.

Reduce Loads
Energy-efficiency experts often agree that the first step in increasing HVAC energy conservation (before retrofitting or replacing HVAC systems) is to reduce loads. One way to do this? By investing in low-e window film. According to the U.S. Department of Energy, solar heat gain from windows is responsible for almost one-third of a building’s cooling costs. Window film may significantly reduce this number.

While curtains or drapes help block sunlight (keeping interior temperatures cooler in the summer), they still let the summer sun’s heat into the building through the glass. High-performance, low-e window film reduces the amount of solar heat gain entering the building, which keeps interior spaces cooler in summer (and reduces cooling energy usage.)

In the winter months, high-performance window film may improve HVAC energy efficiency by decreasing thermal heat loss through windows, keeping spaces warmer.

Have you tried any of these solutions? What other ways have you found to improve HVAC energy usage year-round?


  1. Rick Nauseef
    December 20, 2014

    I utilize the BMS ( Building Automation Systems) Using time schedules to do temp setbacks when areas are not being utilized. Also have started using sensors for occupancy and temp set points.

  2. Vista
    December 23, 2014

    Rick, that’s a great idea. Sounds like you’ve got a good handle on managing your HVAC system for efficient performance!

  3. Zach
    March 12, 2015

    I didn’t think about making sure the vents are all clear and open when we have the air coming through. A 25% energy increase is a lot of money that goes right down the drain. We will have to look at trying to do something to unblock all of our vents. I know right now a lot of the furniture sits on top of our vents. I thought it wouldn’t cause any trouble as long as the air was able to flow out of the vent. This would explain why our heaters in the winter run a lot and we don’t feel the house head up at all.

  4. Vista
    March 17, 2015

    Zach, thanks for your comment. You’re right – increased energy is essentially money going down the drain. Glad this information could help you!

Leave a Reply