Building Tune-Ups: What You Don’t Already Know

11Feb2020
BY Burns Mechanical IN Energy, Philadelphia Benchmarking, Service

On December 10th, 2019, Philadelphia Mayor Jim Kenney signed the Building Energy Performance Policy, requiring owners of certain large buildings over 50,000 square feet to conduct tune-ups of the base energy and water systems.  It is expected that implementation of the policy will cut carbon pollution in the city by nearly 200,000 metric tons, equivalent to removing 40,000 automobiles from our roads.* However, many of our clients are asking what they should expect as building owners.

Building tune-ups bring opportunity for low-cost improvements with short return on investment that result in enhanced occupant comfort, reduced energy usage and costs, and prolonged life of equipment. The focus of a building tune-up is to ensure that the base building systems are operating optimally, whether usage and occupancy patterns have changed, components need repairs, or the systems weren’t commissioned properly from the start. We’ve seen building owners benefit from simple tune-up projects in all of these scenarios- and we’ve learned a few important lessons along the way.

 

An infrared image shows an improperly constructed thermal enclosure causing chronic temperature control problems.

Savings Can Be Found in Unexpected Places

The underlying principle of the Building Energy Performance Policy is that the average commercial building wastes 30% of the energy it consumes which suggests a large window of opportunity to improve efficiency. Though there are a number of reasons that waste occurs, any of our engineers could tell you how often they see systems and enclosures that just weren’t commissioned properly to begin with- it happens more often than you’d think. In one case chronic temperature control problems, intuitively thought to be caused by poorly functioning HVAC systems, were actually the result of an improperly constructed thermal enclosure. Infrared scans identified a thermal bridge at the steel-masonry interface, causing the ceiling cavity temperature to drop significantly. The problem was solved through a simple and relatively inexpensive insulation project. Whether your energy savings are realized from building envelope improvements, miscellaneous HVAC tweaks, updating controls, or lighting replacements, tune-ups can cut energy usage by 10-15% on average and pay back the initial investment within 2-3 years.

 

Create a Realistic Plan

Though tune-ups are usually low-cost measures that pay back quickly, it’s inevitable that you’ll encounter unforeseen costs after the initial inspection is completed. For instance, initial data monitoring and engineering inspection might identify improper operation of an HVAC airside economizer cycle. When conducting the actual re-commissioning of the system, however, technicians discover a failed damper actuator and blade seals. We typically recommend a contingency allowance of 10% to 25% in addition to the initial tune-up cost estimate, depending on the anticipated scope of work. The contingency allows the additional repair work to be completed without interrupting the project schedule. On a recent large-scale tune-up project, miscellaneous repair work amounted to just shy of 15% of the blue-sky cost estimate. Unforeseen costs were reported and approved routinely to keep the owner apprised of progress.

 

Tune-ups Are a Team Effort

To get the best return on investment from a building tune-up project, it’s important to take a holistic look at energy consumption. This requires the expertise of both a technician and a qualified tune-up specialist. An open line of communication between the parties through the entire process ensures that all components are brought into alignment without creating new conflicts. Our tune-up projects are structured to facilitate this combined effort between our Professional Engineers and Service Technicians, while providing a seamless process and single source accountability to our clients.

 

 

*https://www.phila.gov/2019-12-10-mayor-releases-energy-benchmarking-report-and-signs-green-legislation/