Ongoing commissioning ensures energy efficiency
Mechanical, electrical, plumbing, and fire protection systems must be engineered and commissioned so that the Dept. of Veterans Affairs has control over the system and so continuous measurement and verification are possible.
- Understand the Energy Independence and Security Act, and how it affects federal buildings.
- Learn ways to retro-commission a building to achieve additional energy efficiency.
- Understand the steps to ongoing commissioning.
In 2010, the Dept. of Veterans Affairs (VA) Southeast Network (known as VISN 7) energy management office embarked on a program to comply with the retro-commissioning requirements of the Energy Independence and Security Act (EISA) law. The 2007 EISA law and the executive orders issued pursuant to this law mandated that all federal agencies reduce energy by 30% under the 2003 energy baseline usage (Executive Order 13514 and Executive Order 13423). Leveraging information from a 2009 Retro-commissioning Training Seminar conducted by the National Environmental Balancing Bureau for the VA Energy Managers group in Little Rock, Ark., VISN 7 constructed a retro-commissioning program to evaluate and improve the 8.6 million sq ft of hospital and medical support facilities within the network consisting of 10 hospital campuses.
Beginning in 2010, VISN 7, in collaboration with Sebesta, executed a retro-commissioning program for the 10 VISN 7 campuses that included:
- Intensive evaluations of each of the 10 VA campuses in Georgia, Alabama, and South Carolina included in VISN 7
- Implementation of low- and no-cost improvements in components, systems, and operating strategies
- Training of the network operators responsible for operations of the 10 campuses
- Implementation of strategies to improve compliance with VA standards and energy efficiencies in achieving compliance.
Over the subsequent 3-year period of execution, the retro-commissioning team identified and implemented energy and performance improvements that resulted in an average 13.6% energy savings across the 10 VISN campuses with a simple payback on all costs of 3.18 years. Table 1 summarizes the net impact of this program.
Sustaining the result
As the retro-commissioning effort proceeded to its conclusion, the VA Southeast Network Energy Manager recognized that the bigger challenge in complying with EISA was sustaining the results achieved in the retro-commissioning effort. Like any large real estate portfolio, the operation of large energy-consuming systems is most often compromised by a combination of factors, including:
- Normal deterioration of mechanical equipment and systems
- Inappropriate or incomplete maintenance response to system failures
- Occupant complaints solved by expedient compromises of system operating strategies
- A return to outdated operating methods based on "years of experience" operating familiar buildings.
This deterioration in system performance can be exacerbated if sufficient funds and/or contracting processes are not available to correct component failures that normally occur in a building. Finally, the cultural attitudes that make efficient resource allocation a value in each facility must be periodically reinforced so that the good practices established in the retro-commissioning process are not overwhelmed by comfort complaints and special circumstances that lead to compromising these good practices.
For example, when comfort or compliance complaints occur, it is often necessary for the operations team to override normal operating conditions temporarily while the appropriate corrective action is implemented (a schedule override or a setpoint adjustment outside normal conditions). The Constant Commissioning and Reporting System (CCRS) monitors these conditions to identify these temporary adjustments and encourage early implementation of the most cost-effective and energy-efficient corrective action necessary to return the system to its proper mode of operation.
In the recently published "Dept. of Veterans Affairs, Retro-commissioning Process Manual" (May 1, 2014), the retro-commissioning process as envisioned by the VA includes a "persistence phase." The system described in this article addresses the specific objectives outlined in this newly published manual.
In 2012, VISN 7 initiated a program in collaboration with TL Services and Sebesta to institute an "ongoing commissioning process" that would support the operations teams in the 10 VA campuses within the VISN. The process was to be supported by a monitoring-based ongoing commissioning system to provide oversight of the VISN’s 8.6 million sq ft of medical facilities. The specification for this system was developed to provide both oversight and reporting to the operations team and an intelligent alarming system that could be used to provide the first level of failure analysis. The objective was to provide operators with specific recommendations for addressing and resolving operating alarms when they occurred.
Objectives of the program
The objective of an ongoing commissioning process is to provide support and accountability for the operations team at each VISN 7 site for maintaining effective hospital operations while optimizing energy consumption in each campus building. The process is intended to address the traditional issues that impede effective operations and maintenance of energy consuming systems. The process is designed to achieve, at a minimum, the following objectives:
- Provide technical solutions (software data acquisition, analysis, and exception reporting tools) that provide visibility of system performance deficiencies in a user-friendly manner.
- Establish periodic reviews with third-party technical support for the operations team to create space in the team schedule to analyze system performance. The periodic reviews provide the opportunity to revisit current processes, establish best practices, and reinforce staff training.
- Provide a budget and execution mechanism to execute corrective actions to repair or upgrade system components that fail or deteriorate to the point of compromising system performance as part of the periodic review process.
Ongoing commissioning process
Based on this planning, the VA team issued a solicitation to engage professionals to implement a process of technical analysis and staff support. The process was implemented to accomplish the following tasks:
- A data acquisition and analysis software package was installed by TL Services to provide an effective exception reporting tool for the operations and ongoing commissioning team. The Web-based software allows the energy management and operating teams at each site to review the entirety of their large campus system by examining only those components that are operating outside the boundaries of acceptable systems operating parameters. Further, each site can review its performance as compared to other sites within the VISN to gauge its success in operating its facilities.
- Rules have been developed and evaluated and continue to be enhanced through collaboration between the VISN Energy team, the TL Services team, Sebesta, and the site operations teams to provide the most important information necessary to both comply with VA operating standards and optimize energy usage at each site.
- The TL Services team in collaboration with the site energy managers and operations teams regularly review both exception reports and overall system operations checkups. The checkups are designed to provide both technical support for analyzing exception reports and trended performance data and to provide additional training to reinforce good team practices.
Over the course of implementing the contract to provide an ongoing commissioning process, the TL Services team developed a Web-based software tool rooted in the most prevalent technologies currently being employed in the building control industry. The system is based on Niagara technology for interrogation and accumulation data from both energy metering and automated building management systems installed in the VISN facilities. The interrogated building management systems include legacy systems, both proprietary and Web-accessible systems, from Siemens, Johnson Controls, Honeywell, Alerton, Automated Logic, and Trane control systems.
Data is uploaded to a cloud-based server for analysis in the Niagara software package and displayed for all VISN users and the TL/Sebesta site support team. Within the cloud-based database, information is analyzed for both display and exception reporting purposes.
The team implemented a set of rules against which the operating data is analyzed daily. The system, while it is not intended to provide real-time operations, does provide analysis that is no more than 24 hours old. Historically, data can be stored for a minimum of 2 years to allow historic comparisons for energy, water, and critical system performance characteristics. This tool will allow the system to become smarter over time by making operations and performance data easy to access and analyze.
The exception rules have been designed to both recognize deviations from VA standards and provide analysis of operating data that surround the deviation. The development team recognized that these deviations from standard operating conditions and/or historical operating values are the best early warning indicators of system failure. Further, deviations from standard setpoint and schedule conditions can act as a reminder to the operations team to restore "default" settings and schedules when temporary overrides are forgotten or overlooked.
The additional analysis is intended to provide operators reviewing the data with work tasks that are appropriate to addressing and correcting the identified issues. Exception rules may be as simple as a comparison with historical energy usage data with recommendations to evaluate specific energy usage patterns in the previous quarter. Or they may entail an automated evaluation of multiple data points to determine a most likely cause of failure. The resulting recommendations, incorporated directly into the exception report, provide the operators with specific task guidance to drive a physical response by the operating team members.
In addition to its exception reporting functions, the CCRS also provides reporting functions that give an overview of the system operations, an evaluation of operations against both target objectives and similar VA facilities within the VISN 7 network, and a high-level evaluation of the overall condition of each facility.
At the highest level, the current energy and water resources consumed at each campus are displayed against the target values for each resource. The target values are those consumption values mandated by EISA and Executive Order 13423. The graphic display allows each user to examine each utility individually and aggregated total site energy consumption. Performance of each site as compared to target values is displayed with utility buttons at the bottom of the graphical display-green when energy consumption is below target, red when above. In addition to individual site graphics, the system provides an overview of all 10 campuses within the network. Again, campus performance against targets is displayed with color-coded buttons. Comparative energy usage indices (EUI) are displayed along with usage of individual utility’s sources.
Finally, the VISN overview screen displays the total number of active exceptions for each campus. It is these exceptions that will guide the operations team to understand the source of operating deficiencies and strategies to correct them.
Drilling down to each site, individual exceptions are displayed along with recommendations to correct the identified issue. Just as important, the daily cost of allowing the deficiency to persist is calculated and displayed on the exception reporting screen. The cost avoidance values displayed for each deficiency are part of an overall strategy to put the cost of maintenance into perspective-if a repair can be completed, the overall cost to the site will be reduced.
Support for ongoing commissioning
As part of the ongoing commissioning process, the TL Services support team will provide technical support for the site operations teams to both understand and implement CCRS recommendations. The technical support will provide support for the operations team, continuing training to the operators, and support for implementation strategies to assure that the information provided by the system is converted into action. Technical support will consist of both weekly conference calls and periodic site visits by qualified engineers and technicians. The objectives of this ongoing support include:
- Review the exception reports with the operations and maintenance (O&M) team to verify that the information provided by the reports is clearly understood. Reinforce training in reading and understanding the information provided by the tool and in determining the appropriate response to that information.
- Review any corrective action items created by the O&M team based on the exception reports reviewed by that team. Confirm that corrective actions are being created and acted on by the O&M team.
- Develop additional corrective action items based on a detailed review of the campus operating systems. Create alternative execution strategies for each item or group of items to facilitate component and systems repairs necessary to sustain performance.
- In collaboration with the VISN energy managers and site personnel, facilitate execution of significant corrective actions by either on-site personnel or service contractors. Validate the proper completion of each item.
- Review with site personnel service contract records and performance to validate that active service contracts are being fully executed and delivering value to the site.
- Reinforce training and recommend additional third-party training for O&M personnel to supplement their technical skills necessary to sustain performance of the installed systems.
Future of the CCRS
Beyond the considerable benefits of the installed CCRS ongoing commissioning system, continuing development of the technology embedded in the technology tools will allow for further integration of the exception reporting system and the site’s maintenance management system. As with all technologies, the next logical steps in the evolution of technology support for our operators is to generate maintenance work orders-both predictive and responsive work orders-and provide summary cost reporting to support the cost-effectiveness of a robust maintenance operation at these complex medical facilities. Integration with smartphone and tablet technologies will make the information provided by this system more portable and accessible. Integration with BIM systems, with electronic O&M manuals, and with computerized maintenance management systems (CMMS) will provide a greater focus and a greater efficiency to building operations throughout the VISN 7 Network.
Reducing energy usage index by 3% annually
In accordance with Executive Order 13423, each Dept. of Veterans Affairs campus is obligated to reduce its annual energy usage index (EUI) by 3% per year from the FY 2003 EUI with the reduction target starting in FY 2006. This corresponds to a target of 21% below the 2003 EUI in FY 2012 and 24% in FY 2013. The objective of the retro-commissioning project was to achieve EUI reductions of 10% to 15% below FY 2009 consumption values. Results are reported for both objectives.
System performance deficiencies
Examples of system performance deficiencies include deviations from setpoint standards, occupancy schedule standards, and well-established performance criteria such as discharge air temperature setpoints, outdoor air volumes, chilled water temperatures, and energy consumption profiles.
What is MBCx?
Monitoring-based commissioning (MBCx) employs remote energy system metering with trend log capability to identify previously unrecognized inefficiencies in energy system operations, facilitate the application of diagnostic protocols, document energy savings from operational improvements, and ensure persistence of savings through ongoing recommissioning. Definition from: Monitoring-Based Commissioning: Early Results from a Portfolio of University Campus Projects", Brown et al., National Conference on Building Commissioning, 2006.
Outdoor airflow station management
As a normal part of any retro-commissioning effort, outdoor air values are adjusted to minimum flow to validate that each air distribution system is adequately ventilating the spaces served. This process assures compliance with ventilation standards. It also optimizes energy performance by limiting ventilation whenever its sole purpose is indoor air quality (IAQ) management. Outdoor air is often managed by flow stations installed in the air distribution system. These flow stations, which are responsible for a substantial portion of the heating and cooling load in a typical system, require consistent maintenance and care. Yet they are often found during retro-commissioning to be inaccurate or unusable.
The continuing certification requirement system (CCRS) was designed to allow the operator to observe and manage outdoor air control on an ongoing basis. While outdoor air is managed by the flow stations, evidence of their proper operation can be validated through a combination of return, mixed, and discharge air temperature measurements. Further, outdoor air damper operating positions can be tracked over time to confirm that whenever the system does not require economizer cooling, the outdoor air quantities are operating within an acceptable range.
In the Dept. of Veterans Affairs Southeast Network (known as VISN 7), the accuracy of the outdoor airflow stations is validated by temperature measurement of outdoor air quantities whenever the system is operating at minimum flow settings. Using return air, outdoor air temperature, and mixed air temperature, an estimate of the outdoor air quantity can be calculated and compared to the outdoor air setpoint value. When the calculated and measured values differ by 15% or more, the operator is alerted to inspect the outdoor airflow stations and to confirm by measurement that the flow stations are operating correctly. Guidance is provided to calibrate the flow station if the investigation indicates a need.
Jerry Bauers is vice president at Sebesta Inc., and is a member of the Consulting-Specifying Engineer editorial advisory board. Terry Looper is president and CEO of TL Services. Paul Morgan is Southeast Network Energy Manager and an employee of the Dept. of Veterans Affairs. The views expressed in this article do not necessarily represent the views of the Dept. of Veterans Affairs, the Secretary, or of the United States.