Monitoring-based Cx frequency of analysis and approach clarification

Kevin, 

I can see why you raise the question. The reference guide seems to simultaneously indicate that analysis needs to be conducted in real time (continuously) but then also that the analysis needs to occur at a minimum, quarterly. That said I think that your approach would work given the mix of real-time feedback on equipment operations via the BAS and more in-depth quarterly review of data. The only piece that I see that could be missing is real-time energy analysis component to your plan. As a practical matter, quarterly energy analysis doesn't seem frequent enough to match the credit intent. 

When thinking about meeting the credit intent, I found this content from the reference guide language to be informative. "In other words, MBCx allows the user to track energy consumption, detect faulty equipment operations, and identify unusual energy or power consumption patterns as they occur." 

Good points and questions related to a lack of guidance from the standard. In many ways, looking to the intent of the credit is as important as the text. In this case, having an immediate response from trends, alarms, or other messages is important to a monitoring plan. Many of the action items from the original Cx should be a basis for developing these alarms. One example, we all find critical setpoints in a process that if changed have a dramatic effect on the operation and efficiency. Even having a warning that as setpoint has changed should be considered part of a plan.

That being said, as you think about continuous Cx, having a team of the maintenance crew along with management and others meet on a quarterly basis to discuss energy performance, trends, alarms, and any other performance issues seems appropriate and would comply with the intent of the credit.

I agree with Kevin that quarterly review of energy is not enough. Having a monthly running 12-month measurement of performance with as much detail as possible should be done to review trends of the systems drifting from the as commissioned performance. A derivation of a certain amount should trigger a meeting and further investigation and analysis to determine what might be happening.

I am by no means an expert in this area and have been struggling to clarify scope of MBCx as well. The Reference Guide states "The real-time analyses can be performed by either a service provider or an on-site energy manager who uses software to monitor data from building meters and the building automation system." "The analysis must be performed at least quarterly. The MBCx should include an action plan for identifying and correcting operational errors and deficiencies." I take this to mean additional software performing fault detection data analytics is not required to achieve the credit.

In general, I try to look at the goals of a given LEED requirement. In this case, I think the focus should be on the process and results, then the tools applied will depend on many factors, complexity of system, skills of owner and operators, budget, etc. The most successful MBCx that I have seen were a combination of the DDC system having key indicators of performance that are monitored real-time, then monthly reviews of more detailed information including simulations and historical records. As a operations team becomes more experienced with a system and building, the monitoring, alarms, and tools will most likely change. Every building is unique and will reveal its operating sweet spot over time.