Monitoring-Based Commissioning Basics
Published by David Lippe
If you have been following the trends in energy efficiency over the past few years, you will have likely caught wind of monitoring-based commissioning or MBCx. You may have even heard it referred to as “continuous commissioning®” (the phrase trademarked by Texas A&M), ongoing commissioning, or any number of creative titles.
Monikers aside, the service of MBCx is driven by a tremendous flow of building data that must be analyzed by robust performance computations. So let’s dig a little deeper, but I promise (hope) I will only keep you for about 5 minutes. The remainder of this blog post will cover the elements involved in monitoring-based commissioning, the benefits, and how you can get started.
No small task indeed!
The frequency and volume of data necessary to accomplish a comprehensive list of performance improving opportunities can be a bit mind-numbing. So let’s play with some quick numbers.
Say your building has an automation system that manages 1,000 data points between temperatures, pressures, speeds, and positions. If you monitor all of that at 5 minute increments, you’ll have over 1.4 million pieces of data in a single day! It’s difficult to imagine manually processing this bulk of info while also maintaining a role as a Building Engineer or Property Manager.
What do you need?
To manage that amount of data with any kind of certainty (read sanely) you need tools. Specifically, you need tools that are able to collect, map, and scrutinize the data related to your HVAC equipment on an ongoing basis. Then you need that system and a service provider to identify issues, generate ideas, and propose opportunities. You need it to do that because in the 21st Century these programs can be used to improve maintenance operations and save on energy costs. In fact, it can do all of that and even get to predictive maintenance.
Other points and items can be drawn in here as well and can typically be fully customizable based on your needs and interests. But what we have very casually described here is an Energy Management and Information System (EMIS).
Energy Management and Information Systems can be further broken down into what are called Energy Information Systems (EIS) and Fault Detection and Diagnosis (FDD) systems. The U.S. Department of Energy defines EIS and FDD as the following:
Combine these two components with an energy efficiency service provider and you have a recipe for significant energy savings, energy cost savings, avoided costs, and improved building health.
Why would you do it?
Numerous studies have proven the value of employing this in-depth, multi-faceted approach to achieving low- and no-cost operational savings. Experts from Lawrence Berkeley National Laboratory (LBNL) wrote on the subject as early as 2009 as a way to avoid the inevitable “drift” in building performance as systems and equipment age.
The graphic below, taken from the LBNL study on “Building Commissioning” published on July 21st of that year, illustrates the performance of a typical office building over time and overlays the different stages of benefits from and differences between retro-commissioning (RCx) and MBCx.
Shown in a light yellow, RCx is a one-time, periodic “tune-up” of a building that leverages a snapshot of performance data. As the building operates over a few years post-RCx, it falls out of calibration and can benefit from RCx again and again on this cycle.
By implementing MBCx, those “drifting” building performance characteristics are avoided and represented by the seafoam green in the graphic. Further still, the lavender layer below captures the immediate impact (first 6 months) of MBCx from identifying previously undetected HVAC issues and lingering operational problems. Finally, the MBCx EMIS grants the building additional operational savings over time as occupancy and space use change, coupled with improved visibility to the building’s performance.
Bringing it all together
As the ENERGY STAR analytics for building performance clamps down and the criteria for specialized building certifications, such as LEED, become more and more challenging, more sophisticated methods of obtaining operational energy savings in existing buildings are paramount.
Local utilities, including ComEd here in Chicago, offer an incentive program to integrate these robust fault detection tools and analytics programs with the promise of energy savings.
While it may all sound overwhelming, there’s no need to get mired in the details. That’s what you hire us for. To find out more about MBCx, contact us at firstname.lastname@example.org.