A: The old saying, "What you don't know will kill you" applies perfectly to managing existing facilities. Clean manufacturing facilities with their additional layers of complicated building and process systems magnify that truth.
Buildings and their systems are designed to perform to specified standards. However, as time marches on, this performance degrades or systems are modified, and many times those modifications aren't documented. The result: Building performance declines, energy usage increases, and the operations budget takes a wasteful hit.
A previous column, "Building Commissioning: Real or Smoke & Mirrors?" (Controlled Environments, May 2011) examined the commissioning process. This column will examine the unique considerations of commissioning an existing facility.
The term "retro-commissioning" commonly is used to refer to the commission of an existing building that has not previously been commissioned. Retro-commissioning is one scope of Existing Building Commissioning (EBCx). The Building Commissioning Association (BCA) defines Existing Building Commissioning as: "… a systematic process for investigating, analyzing, and optimizing the performance of building systems through the identification and implementation of low/no cost and capital-intensive Facility Improvement Measures and ensuring their continued performance. The goal of EBCx is to make building systems perform interactively to meet the Current Facility Requirements (CFR) and provide the tools to support the continuous improvement of system performance over time. The term EBCx is intended to be a comprehensive term defining a process that encompasses the more narrowly focused process variations such as retro-commissioning, re-commissioning, and ongoing commissioning that are commonly used in the industry."
Retro-commissioning is typically driven by three objectives: reducing energy use with resultant operational savings, safety/security, and the comfort of the building's occupants. These objectives fall under the main goal of commissioning: to verify and document that the facility systems function as the original design intended. Manufacturing facilities—and particularly clean manufacturing facilities—introduce another layer of complexity to any retro-commissioning undertaking, given their complex process utilities to consume vast amounts of energy. Historically, commissioning was developed with a strong focus on building HVAC systems.
In their Best Practices in Commissioning Existing Buildings guide, the BCA outlines the purpose of existing building commissioning as to:
• Verify that a facility and its systems meet the CFR
• Improve building performance by saving energy and reducing operational costs
• Identify and resolve building system operation, control, and maintenance problems
• Reduce or eliminate occupant complaints and increase tenant satisfaction
• Improve indoor environmental comfort and quality and reduce associated liability
• Document system operation
• Identify the operations and maintenance (O&M) personnel training needs and provide such training
• Minimize operational risk and increase asset value
• Extend equipment life-cycle
• Ensure the persistence of improvements over the building's life
• Assist in achieving LEED for existing buildings
• Improve the building's Energy Star rating
Regardless of purpose, goals, objectives and systems complexity, the payback against investment can be fast and significant, in terms of operations costs (both saved and avoided) and energy consumption, as well as increased productivity driven by improved employee comfort and health. While the payback period for a retro-commissioning investment is influenced by the age and complexity of the building and its systems, building size, manufacturing system and process complexity, as well as the scope of investigation and remediation, the basic retro-commissioning process remains the same.
Retro-commissioning also provides facilities managers with an ongoing building maintenance toolbox filled with baseline system performance data, defined performance criteria, and the structure through which to continuously track, evaluate and adjust systems performance. This is important, as commissioning should not be considered a one-off effort. To maximize its benefits, commissioning should be viewed as an iterative and ongoing process. Facilities engineers should consider re-commissioning their buildings every 3 to 5 years.
Because retro-commissioning is an ongoing process and drives superior operations and maintenance practices, it's important to ensure that all key stakeholders understand the process and benefits of EBCx and are vested in the process.
A facility's senior management, operations and maintenance departments, key manufacturing engineering personnel, and any equipment vendors with ongoing relationships to a facility should be on board. It is often advantageous to have representatives of key occupancy groups participate, or at the very least, they should stay informed about the progress. An EBCx consultant should be an independent, certified CxA professional, not someone working for a current contractor or equipment supplier—and not a member of the facility's operations and maintenance staff. The commissioning agent should function as an independent expert and as an owner's advocate.
How do you structure a retro-commissioning project? Again, the BCA offers some advice for phases and goals in its Best Practices guide:
• Planning: Develop the EBCx goals, facility requirements, and a commissioning plan
• Investigation: Conduct field inspections, gather data, test, and analyze to assess system performance and identify improvement opportunities
• Implementation: Complete the desired facility improvements, and verify the results and performance
• Turnover: Conduct a systematic transition from a commissioning activity and the commissioning team to standard operating practice and the operations and maintenance team
• Persistence: Implement systems and tools to support both the persistence of benefits and continuous performance improvement over time.
Investment in staff training during the turnover phase is critical to success. Once the opportunities for improved performance are identified and rectified, it is very important to ensure that the operations and maintenance staff is thoroughly trained. Failing to do so puts the investment in retro-commissioning at risk. Videotape training sessions so new staff members can be easily brought up to speed.
Ensuring that the buildings are operating as intended, while optimizing energy and operations cost efficiencies, are core requirements that link a facility engineer's efforts to a company's business success.