Commissioning commercial buildings: Sustainability, energy efficiency
Ideally, all nonresidential buildings would be commissioned, and the team would start at the onset of the project. Because that’s not always the case, commissioning authorities and experts offer advice on building projects in various stages of commissioning, recommissioning, or retro-commissioning energy-efficient buildings.
Mark A. Gelfo, PE, LEED Fellow, GGP, CxA, EMP, Principal/Vice President, TLC Engineering for Architecture, Jacksonville, Fla.
James I. Givens, CxA, EMP, Division Manager, Field Services, RMF Engineering Inc., Baltimore
Jim Huber, CEM, CDSM, CMVP, LEED AP, NEBB CP, President, Complete Commissioning, Annapolis, Md.
Brian Lindstrom, PE, DCEP, National Director of Commissioning, Burns & McDonnell, Kansas City, Mo.
Paul Meyer, PE, CBCP, LEED AP, CEM, GBE, Senior Vice President, WSP, New York City
CSE: Energy efficiency/sustainability is often the No. 1 request from building owners. What net zero energy (NZE) projects and/or high-performance buildings have you recently commissioned?
Gelfo: We have had very few NZE buildings to commission (only one), but countless buildings we commission are high-performance buildings with aggressive energy-performance goals. One recent example is the Heavener Hall Warrington College of Business Administration at University of Florida (UF). This 57,000-sq-ft classroom and office building has high LEED certification targets of Gold or Platinum with equally aggressive energy efficiency targets both in terms of real energy-use intensity (EUI) and the percentage of reduction as compared to baseline. The project included strategies such as active chilled beams, advanced lighting-control systems, and thermal-envelope commissioning to reduce the building demand load as much as practical. But UF knows that complex buildings need fine-tuning and refinement and the university routinely insists on a rigorous commissioning and M&V program over the first year, sometimes two, of post-occupancy before moving into a recommissioning and M&V program. This is a continuing trend we see toward much more focus on ongoing building performance. Commissioning, retro-commissioning, and recommissioning will have a major role in helping owners verify that their buildings are actually performing, not just after construction, but on an ongoing, continual basis.
Huber: We are currently involved in a retro-commissioning effort in a high-performance building in Washington, D.C. The building was initially commissioned by another firm from out of town last year, but the performance of the building has not met the owner’s expectations, both in terms of energy performance and comfort. Many of the things we identified on our first day on the project are things that should have been caught and corrected very early in the project. This is a project that appears to be headed toward litigation in the near future.
Meyer: We commissioned a small mixed-use NZE building. The owner was also the architect and wanted to showcase his talent. The building contained very highly insulated walls, photovoltaics (PV), a small wind turbine, and ground-source heat pumps.
Lindstrom: We’ve commissioned hundreds of NZE and high-performance military facilities across the country as a part of LEED Silver, Gold, and Platinum programs during the past few years. The designs have frequently taken advantage of wind turbine, PV array, geoexchange heat pumps, VRF, insulated concrete, and other high-performance technologies. We’ve also commissioned a number of utility-provider and health care campus central-utility plants using combined heat and power technology to take advantage of energy savings as well as mission critical reliability.
CSE: Many aspects of sustainability require building personnel to follow certain practices to be effective. What, if anything, can a commissioning agent do to help increase chances of success in this area?
Givens: CxAs can assist and enhance facility operations training. This is not necessarily basic building systems operations and routine maintenance training (which all too often is the sole focus of abbreviated project requirements). Instead, the training should provide building occupants and operators with a comprehensive understanding of the respective facility capabilities, expectations, and limitations. People (and the facilities that they operate within) are far more likely to operate efficiently when they are well-informed. Commissioning providers are uniquely positioned to be involved in all aspects of sustainability as they relate to buildings—from initial design concepts (and what factors may influence the design one way or another) through construction, initial operations, varying seasonal conditions, acceptance and occupancy, warranty periods, and ultimately beyond. Involving building users and facility operators throughout this entire process as part of the commissioning team, while driving a fundamental understanding of facility and systems design intent(s), performance expectations, and operating sequences/protocols, is an invaluable attribute that CxAs can contribute to driving the success of ever-increasing sustainability goals in the built environment.
Meyer: Training, training, training, followed by more training. Nothing kills the efficiency of a building more than staff making changes without understanding the operating effects. Making one complainer happy can often throw an entire system out of balance.
Lindstrom: The CxA can verify the O&M staff is properly trained on how the building was intended to operate rather than just how to perform routine maintenance procedures. One proven way is for the CxA to formally provide this training and allow O&M staff to witness commissioning-related testing. It is also beneficial to add documentation and detail to the BAS with detailed explanations on why certain setpoints were chosen or what the impact could be if they are changed. For existing facilities being retro-commissioned, a best practice is for the CxA to work with O&M staff early to understand their maintenance procedures and how they currently operate facilities. With this understanding, the Cx process and training are tailored accordingly.
Huber: Hands down, the best way to ensure that building personnel learn their systems is to have them involved at a hands-on level in the commissioning process—especially site inspections and functional testing. It can be a challenge to convince the building owners of this, especially if they use a third-party property management company, but this experience is worth its weight in gold. When that can’t be done, do not underestimate the value of a quality training seminar. This means a seminar that includes some level of basic theory in system design and operation—not just a seminar of how to troubleshoot or operate specific equipment. Lastly, the more successful a project is, the more likely that the owner will relocate that operating staff to a lesser-performing building in his portfolio. For that reason, all training sessions should be videotaped, and that also should be done at a high level if you don’t have the true expertise within your firm. We have found that wedding videographers often need work during the weekdays anyway, and you would be surprised how economical that avenue can be when you offer them 3 to 4 days of steady work.
CSE: Please share a retro- or recommissioning success story in which you were able to enhance sustainability of a building. Annual statistics on energy savings and other supporting evidence would be helpful.
Meyer: I can almost predict the success of the retro-commissioning project at the kick-off meeting. Retro-commissioning success is closely tied to the building operating staff. Some staff members are eager and driven to do the best, and some are a detriment. We worked with one Energy Star-certified building whose operating staff always asked for “ways to save another nickel or dime.” Another good building operator said, “I don’t want you to leave until you show me how to optimize my chiller plant.” Poor building staff members don’t want to be bothered. They unlock an equipment room for you and then disappear.
Gelfo: We are nearly finished with retro-commissioning an Energy Star building that we believe will increase building efficiency significantly. The EverBank Center in Jacksonville, Fla., is a 1-million-sq-ft, 32-story Class A office building that is already Energy Star-certified, having been certified in 2009 and 2011. We helped the owner upgrade the original 1984 pneumatic-controls system to a state-of-the-art BAS, and in the process systematically retro-commissioned each floor’s AHUs, VAV boxes, setpoints, outside air operation, and the chiller plant. The AHUs and boxes are integral to the building smoke-control system, so we also worked very closely with the local fire marshal throughout the retro-commissioning process to ensure that life safety operations were properly maintained. We benchmarked energy usage prior to beginning the retro-commissioning process; with the increased controllability of the new control system and corrections and adjustments made throughout the retro-commissioning process, we estimate the owner will see a 10% to 15% improvement in energy efficiency, on an already Energy Star-certified building.
Lindstrom: We recently completed retro-commissioning for more than 4.5 million sq ft of facility infrastructure for Houston Airport System (HAS) at George Bush Intercontinental Airport, William P. Hobby Airport, also in Houston, and the HAS consolidated rental-car facility. Systems and equipment had aged and, in many cases, were never commissioned properly or at all. Optimizing and improving their existing state was essential, in addition to assessing their current condition for asset management purposes. Systems included HVAC, electrical power and distribution, building envelope, architectural finishes, structural, roofing, conveyance, baggage handling, passenger-boarding bridges, ground power, preconditioned air, domestic water, sanitary sewer, fire protection, and building-automation controls. This comprehensive effort involved review of design and record documents followed by interviews with the owner’s staff to gain customer and stakeholder input. The project also required utility and energy analysis, hands-on operational inspections, assessments, systems testing and adjustments, and integrating data into an asset management system. Field data was captured electronically via tablet computers using a custom data-collection tool that combines mobile computing, photographic, GIS, and database technologies to enable condition assessment, energy audit, and retro-commissioning data to be collected simultaneously. Data was integrated (uploaded) to the HAS enterprise asset management system efficiently, accurately, and with minimal effort. We used 22 commissioning specialists to perform the field effort in 4 months. The effort resulted in clear recommendations for capital improvement and asset management as well as more than $1.6 million in identified energy savings.
CSE: Please describe your commissioning experience in smart or intelligent buildings.
Lindstrom: Over the past 2 yr, we have seen a significant increase in client demand for smart building or intelligent building technologies. While little standardization exists between platforms or approaches, we have seen a common theme involving a higher degree of systems integration to proactively justify actionable behavior. This is typically with the goal of energy and/or operational savings. Fault detection and diagnostics (FDD), submetering, demand response, and augmented operations strategies such as rolling trucks to implement batch resolutions are a few of the common tenets of the smart building. Our experience has been program-level assessment and planning, retro-commissioning, cyber security analysis, and technology evaluation for federal government and commercial-facility portfolios.