What is 'Building Energy Drift' and How Much Does it Cost Your Business?
If you own a car, you know that ignoring routine maintenance could put both your car and your safety at serious risk—brakes would stop working, tires would fall apart, or the car would simply stop running. Any of these problems would be significantly more expensive to fix retroactively than what it would cost to perform routine maintenance. Even failing to provide routine tune-ups and oil changes would bring down gas mileage and end up costing you more money.
You should be looking at commercial buildings the same way. Evan Mills, Ph.D., Senior Scientist at the US Department of Energy’s Lawrence Berkeley National Laboratory, analyzed the impact of commissioning and retro-commissioning in large commercial buildings in his report (PDF). Similar to cars or even ships—which Mills references as having employed retro-commissioning practices for centuries—commercial buildings are susceptible to equipment deficiencies and general wear and tear that can cause buildings to “drift” from the ideal operational environment envisioned when the building was initially designed.
As a result of this drift, commercial buildings can see energy efficiency degrade by 10% to 30% over a one- to two-year period, according to research from Texas A&M University and the Lawrence Berkeley National Laboratory. Beyond its impact on energy efficiency, building drift can drive up maintenance costs and capital expenses, disrupt tenant comfort, and lead to equipment issues that pose a safety risk in your buildings.
Mills points to building design flaws, construction defects, and malfunctioning equipment as common causes of building drift, and warns that these deficiencies can lead to equipment failure, compromised indoor air quality, and unnecessary energy use. These kinds of problems can get more expensive the longer they go ignored.
Addressing these problems can have a serious financial impact. By following best practices, Mills estimates that commissioning can “result in zero- or negative net cost as non-energy benefits more than offset commissioning fees,” with the potential to save more than 50% of whole-building energy use.
“Significant first-cost savings (e.g., through right-sizing of heating and cooling equipment) routinely offset at least a portion of commissioning costs—fully in some cases,” Mills wrote in his report. “When accounting for these benefits, the net median commissioning project cost was reduced by 49% on average, while in many cases they exceeded the direct value of the energy savings. Commissioning also improves worker comfort, mitigates indoor air quality problems, increases the competence of in-house staff, plus a host of other non-energy benefits.”
How to Take Control of Building Drift
Among the best practices for commissioning, Mills’ report recommends “a monitoring-based paradigm for identifying and quantifying opportunities on an ongoing basis.” If you can identify malfunctioning equipment proactively, you can avoid unnecessary energy expenses, repeated maintenance costs to fix equipment retroactively, and capital investments when equipment needs to be replaced.
With facility optimization tools, your property-level staff can monitor building performance continuously and receive actionable information to address problems proactively. Investing in the tools to take control of building drift will improve energy efficiency, make your facilities teams more productive, and protect your organization against risk over the long term.
“Commissioning is more than ‘just another energy-saving measure,’” Mills wrote in his report. “It is a risk-management strategy that should be integral to any systematic approach to garnering energy savings or emissions reductions. Commissioning ensures that building owners get what they pay for when constructing or retrofitting buildings, it provides insurance for policymakers and program managers that their initiatives actually meet targets, and it detects and corrects problems that would eventually surface as far more costly maintenance or safety issues.”
Commissioning your buildings will undoubtedly have an impact on energy drift in your buildings, but how you approach commissioning will determine how much of an impact it will have.