Incomplete testing and lack of design review

This police headquarters required an overhaul of its air handlers, building automation system, and lighting system.

12/27/2013


Due to the high energy use at this all-electric police building, exp U.S. Services was brought in to perform retro-commissioning and assess the problems and potential for energy savings. This large, 12-year-old, 5-story building houses the administrative offices for the police department, which was supposedly occupied 24/7. In reality, only a small portion of the building is occupied continuously. Two large air handling units (AHUs) serve the entire building through variable air volume (VAV) and fan-powered boxes (FPBs).

During the inspection, 20 of the 100 perimeter FPBs were found inoperative. These boxes are the only source of heat, and tenant comfort issues were common. Further investigation revealed some incorrect coding in the building automation system (BAS) programming was permanently holding these boxes in “unoccupied” mode. This error was corrected quickly, and all boxes began functioning properly. Although this was not directly an energy conservation item, it allowed the building operators to shut off the AHUs during winter nights because the FPBs would operate independently, and provide heat as needed. It appears that the BAS programming for these particular boxes was overlooked during the initial start-up of the HVAC systems.

The lighting in the building is adequate, and reasonably efficient fixtures were used, but at some point during design, the wall-mounted light switches were “value-engineered” out of the building. The theory was because the building would be occupied 24/7, the lights would never be off, and the switches were superfluous. In reality, only a small portion of the building is occupied continuously and the lights are left on 24/7, wasting large amounts of energy. Area-wide lighting controllers were installed, but subsequently taken out of service due to complaints of lights going off at the wrong times or other problems.

It seems that the proper design review by the CxA would have addressed this issue, and perhaps suggested an alternative design, such as occupancy sensor light switches that would control the local lighting and avoid the current energy waste. exp’s recommendation was to install an occupancy-sensing switch for each lighting circuit in the building. Although a costly option, the annual savings are 1,440,000 kWh and $102,000 for a payback of less than 1 year. 


Terrence Malloy is project manager for the energy solutions group at exp US Services Inc. He focuses on energy conservation, retro-commissioning, and renewable energy systems.



Anonymous , 01/03/14 07:26 PM:

From my experience as a CxA on such projects, I can say with certainty that design review comments coming from a CxA are mostly ignored or forgotten by the design team. They simply don't seem to be able to evaluate and integrate well. They are in the processing mode to get out a design package.
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Robotic safety, collaboration, standards; DCS migration tips; IT/OT convergence; 2017 Control Engineering Salary and Career Survey
Integrated mobility; Artificial intelligence; Predictive motion control; Sensors and control system inputs; Asset Management; Cybersecurity
Big Data and IIoT value; Monitoring Big Data; Robotics safety standards and programming; Learning about PID
Featured articles highlight technologies that enable the Industrial Internet of Things, IIoT-related products and strategies to get data more easily to the user.
This article collection contains several articles on how automation and controls are helping human-machine interface (HMI) hardware and software advance.
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Mobility as the means to offshore innovation; Preventing another Deepwater Horizon; ROVs as subsea robots; SCADA and the radio spectrum
Future of oil and gas projects; Reservoir models; The importance of SCADA to oil and gas
Big Data and bigger solutions; Tablet technologies; SCADA developments
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me