U.S. Department of Energy - Energy Efficiency and Renewable Energy
Federal Energy Management Program
EPA Optimizes Controls at Its Research Triangle Park Laboratory with Real-Time Commissioning
August 28, 2007
The Environmental Protection Agency's (EPA's) Research Triangle Park (RTP) facility has more than 1 million square feet of office and laboratory space. The laboratory space contains more than 600 laboratory modules and 200 fume hoods, while the vivarium (animal holding area) contains 73 laboratory modules, 20 animal suites with 5 surgical areas, and 26 fume hoods. In addition, there are numerous biological safety cabinets and local exhaust systems (canopy hoods) throughout the facility to ensure the safe operation of RTP's laboratories.
While the safety of all RTP personnel is of paramount importance, the systems necessary for maintaining that safety have a significant impact on the facility's energy consumption. Improvements in heating, ventilating, and air conditioning technology have provided an incentive for investigating ways to minimize energy use from these systems, while simultaneously maintaining critical safety features. EPA recently implemented two Controls Optimization Projects at RTP: one for laboratory controls (LCOP) and one for vivarium controls (VCOP). These projects have reduced energy use by minimizing airflow during periods of reduced activity.
EPA tested a sampling of the fume hoods installed during the optimization projects to evaluate their ability to control airflow and ensure the safety of laboratory personnel. Using statistical analysis EPA extrapolated the sample data to establish a baseline flow spreadsheet. Following baseline measurements, LCOP and VCOP required 4 major tasks:
Task 1: Determine minimum acceptable criteria for fume hoods and ventilation controls during both occupied and unoccupied periods.
- Identify laboratories that have the ability to be setback during unoccupied periods.
- Re-calculate optimal airflow set points for laboratories, corridors, and atriums.
- Assess the impacts of airflow changes on system operations.
Task 2: Develop a plan for implementing and continuing new set points for laboratory ventilation controls.
- Develop a commissioning protocol to ensure that new set points are achieved.
- Ensure that laboratories meet EPA performance requirements during occupancy.
Task 3: Implement the approved commissioning protocol in all laboratory modules, animal suites, surgical areas, and associated corridors and atriums.
Task 4: Implement a Static Pressure Optimization and Reduction Test (SPORT).
- Determine the minimum static pressure set points for the supply and exhaust systems.
- Determine optimum sequence of exhaust fan and air handler operation.
The current estimate of airflow savings are shown in this table. (PDF 9 KB) Download Adobe Reader.
EPA has invested $1.9 million in the laboratory and vivarium control optimization projects. A conservative estimate of energy costs for outside air is $4 per cubic-foot-per-minute (cfm), obtained from the Lawrence Berkeley National Laboratories cfm calculator. Even applying this conservative estimate to saving 204,867 cfm provides savings of over $820,000 per year, which equates to a 2.3-year payback period. Expanding the initial project to include ventilation modifications in the corridors and atriums would increase savings to $967,000 and shorten the payback period to 1.9 years.
In addition to the financial benefits of LCOP and VCOP, these projects have provided EPA with less tangible benefits, including:
- Proving the accuracy, repeatability, and reliability of the entire laboratory ventilation system.
- Extending the life of the equipment by performing preventative maintenance on all components of the laboratory ventilation system.
- Providing the Operations and Maintenance (O&M) staff with accurate and extensive documentation for preventative maintenance.
- Establishing protocols for O&M staff that will enable them to quickly and efficiently use the Building Automation System (BAS) to verify and continuously commission the laboratory ventilation system.
As a result of the success of these projects at RTP, EPA has decided to extend the same LCOP and VCOP protocols to its entire inventory of laboratory buildings. A project in Denver is already yielding savings and paybacks similar to those seen at RTP. Numerous other projects are in planning stages and will be implemented as part of EPA's strategy to meet the EPAct 2005's (the Energy Policy Act of 2005's) energy reduction requirements.
For more information, please contact Dan Amon, EPA.