I was cleaning my desk today and came across a napkin on which I’d scrawled some notes about why Building Performance Monitoring and Metrics (BPMM) are important and what the end game in developing building efficiency projects should be.
Measurement without control = looking for buried treasure without a map
A building operator can see that there is a problem, but has no means of finding it.
Control without measurement = shot in the dark
The building operator is making adjustments with no idea of the impacts.
Partners like to see us leave
Energy professionals and building specialists get so involved in our work that sometimes we lose sight of the end game which is to finish the project and get out of a client’s hair.
I appreciate the person who contributed these insights and regret that I didn’t note the source of this wisdom.
It is clear that BPMM address all of the above problems. It provides both measurement and control by fully integrating system and equipment level measurement and metrics with the BMS.
Joe Building Operator notices building energy use creeping up so, with BPMM, he looks at his system level energy use reports and identifies the system where the increase occurred. Since Joe has the right metrics in his BPMM system, Joe uses comparisons between current operations and the established system metrics to drill down and find exactly where the change has occurred. At that point, Joe diagnoses the issue – the energy increase is due to a temperature set point increase that was made by the controls technician last time he was in the building. Joe fixes the set point and makes a note to remind the control tech to reset values after his work is complete.
Jane Building Operator receives a call from the executive wing that the boss’s office is stuffy and hot, so she increases the static pressure set point in a central air handler to get more air up to the 30th floor. That seems to solve the comfort problem, but Jane notices that the energy use has just jumped way above the air handler metric. Based on this information, Jane decides to dig into the issue further and finds that the damper actuator in the VAV box serving the boss’s zone has failed. She gets the actuator replaced and resets the static pressure set point. If Jane had missed the energy impact, a BPMM report indicating the spike in energy use might automatically be generated and sent to the boss who could then inquire about what happened and encourage Jane to dig deeper so she can be comfortable without costing the business unnecessary expense.
BPMM as Treasure Map
BPMM’s ability to alarm or flag issues and send reports enables energy consultants to get out of the building while still providing the owner with assistance in ensuring that their efficiency investments continue to perform and that their employees are maintaining the systems at the optimal level.
BPMM provides a treasure map that can lead to a trove of energy savings. It illuminates the targets so that systems can be fine-tuned over time to maximize performance. And it provides a management tool that helps get the energy experts out of the building while reaping the savings from their work.
For further reading:
"Building Performance Monitoring And Metrics: Putting Building Data To Work." Engineered Systems Magazine, January 2013. Thomas E. Anderson and Jennifer L. Chiodo.