Building Energy Resilience

Previous blog posts from my colleagues and I contain a detailed explanation of functional performance testing (FPT), an overview of how functional performance tests are created, and specific examples of how conducting FPT contributes to better building performance and energy savings.  In this post I would like to expand upon the previous post “Functional Performance Testing Done Right: Details Matter.”

Commissioning agents do a large amount of review of other people’s work and products.  The building commissioning (Cx) process is a quality-assurance process for verifying and documenting that the performance of facilities, systems, and assemblies meet defined objective criteria^[1].  Therefore, to verify facilities and systems, I need access to a product’s technical documentation.  In the commercial building space, almost all documentation is online and readily available via a quick Google search.  Notice that I said almost.

Lighting control systems are making their way into new construction and are becoming as common place as HVAC controls.  Just like with many new building technologies, lighting control systems started small, and are now gaining more and more market penetration.  This is great news for those of us who work towards saving energy for building owners.  This new frontier of controls creates new challenges for those of us who work towards saving energy for building owners.  Why, you ask?

Sometimes, acting as a commissioning authority day in and day out can weigh on you when you hit a streak of projects with dozens of issues that need correction.

We are in the process of wrapping up an energy efficiency and building automation system upgrade project at an office building. The project involved converting an older boiler/tower heat pump loop system with constant speed pumping to variable flow, and the installation of a modern building automation system (BAS) with new energy efficient control sequences. The project has been a big success however, the project team experienced some challenges in really “dialing in” the controls. The main obstacle is that remote access to the BAS had not yet been established. Having remote access to building controls during the later stages of construction provides many benefits—including being able to monitor system performance remotely, review alarm logs and historical trends to identify problems, and even make adjustments on-the-fly to tune system parameters correctly. Without remote access we would have had to drive to the building, request access to a network closet from the property manager, plug into the server in a closet, and then spend time in a tight space trying to accomplish our goals before unplugging and heading back to the office. Needless to say it is not convenient to do frequently, and is expensive.

When you’re asked to review someone else’s building automation system (BAS) programming, it’s a bit of a daunting task.  This is because those of us who program building systems (or really any computer-driven system) for a living figure out that there are a million different ways to capture the same process in any given programming language. Usually no two people will do it the same way.

Building commissioning has become more common on commercial construction projects over the last few years due to the many benefits the commissioning process offers, and in some cases due to new building codes.  During this time owners, architects, engineers, contractors, and construction managers have become more familiar with what commissioning is, and how it affects them.  However, it seems that it’s still often unclear to project teams exactly how to integrate the commissioning authority (CxA) and commissioning process into the construction process.  I believe the first part of the integration begins with communication between the CxA and the rest of the project team. The importance of communication in the commissioning process cannot be overstated.

During recent functional testing of HVAC systems at a healthcare facility, part of our testing scope was to verify room static pressure relationships between adjacent sterile and contaminated spaces. In healthcare settings (and other settings where contamination control is critical) spaces can be designed to have more or less space pressurization with respect to one another—the result is that any air movement between spaces is in the direction from clean to dirty, and not the reverse.

On a recent project we were tasked with trying to reduce the peak electric demand of a building that already had a relatively low summer peak demand of around 40-45 kW and even lower winter demand of around 25 kW.  Immediately ideas jumped into our head that we should look at the four installed rooftop units and the commercial kitchen equipment as sources for peak electric demand savings.

Meter First

Before we began any analysis though, we metered the feed of nearly every electrical distribution panel in the building to check for any anomalies.  We found what was expected – the kitchen and RTUs accounted for a large amount of the electrical demand.   However, when we compared this data with the utility meter (total power of the building) data for the same time period we found that one feed we did not meter turned out to be an important one.

Over the past six months, I have been taking on a new role at Cx Associates as an owner’s Project Manager for a large organization in Burlington, VT. This has given me the opportunity to be part of a construction team - not as part of the commissioning firm, but rather by working for the owner in overseeing the project in its entirety. One of my current active projects is an HVAC mechanical upgrade in an office building known for occupant comfort issues. In this post, I will describe one of the difficulties we needed to overcome with this particular project, as well as a helpful tool that has been very useful for me as a Project Manager.