Laboratory Ventilation Performance: Comparing Centralized Demand Control and Zone-Occupancy Control Systems
Matt Gudorf, LEED® AP, University
of California, Irvine
Geoffrey Bell, Lawrence Berkeley National Laboratory
This presentation provides results from a comparison study of ventilation control in laboratories at the University of California, Irvine (UCI) for their energy reduction and safety impacts. Accordingly, the University of California, Irvine evaluated three air-change-rate reduction scenarios:
1. A centralized demand controlled ventilation (CDCV) system with a design minimum flow of four air changes per hour. In previous testing, the system created a benchmark for use as a comparison for this testing.
2. A simple, zone-occupancy, control-based air change rate reduction system providing 6 air changes during occupied periods and two air changes during unoccupied. For this test the CDCV system was deactivated.
3. A combined test with CDCV and occupancy-based control, providing a minimum of 4 air changes during occupied periods and 2 air changes during unoccupied.
University of California, Irvine installed buttons to override the CDCV system. This feature provided users with the ability to directly raise air change rates during a spill excursion event. As a safety enhancement, local display units inform users of the current status of the ventilation system. In addition, occupancy sensors can lower air change rates to a minimum when workers are not present in the laboratory. Data collection and experimentation provided insight into which combination worked best.
By using a CDCV system, University of California, Irvine has demonstrated the ability to reduce its air change rates from about 12 to six to four. The energy savings are significant. Further, acetone spill testing provided results that showed there was no decrease in safety. New testing was conducted to determine whether occupancy sensors alone could be used as a setback control device without installing a more complicated CDCV system. Data were collected for analyzing how the energy savings of occupancy control alone compared to a CDCV system without occupancy, as well as, in combination using CDCV and occupancy sensing together. During the same period, the University of California, Irvine Environment Health and Safety conducted spill excursion testing to determine whether there were increased levels of risk associated with the three different scenarios being examined.
Results from the study will be shared.
Biographies:
Matt Gudorf is the energy project manager at the University of California at Irvine, a LEED Accredited Professional with 10 years of infrastructure project management experience. A graduate of The Ohio State University in electrical engineering with an emphasis on high voltage systems, Mr. Gudorf has worked for Dayton Power and Light in transmission and distribution, American Electric Power as a member of the ultra high voltage substation design team, and Southern California Pipeline managing multiple wet utility projects throughout Southern California. Mr. Gudorf has focused his efforts at the University of California, Irvine on energy efficiency upgrades, utility and infrastructure retrofits, and project development.
Geoffrey C. Bell, P.E., received his Bachelor of Science in mechanical engineering from Newark College of Engineering. He then went on to receive his Masters of Architecture in environmental design from the University of New Mexico.
Mr. Bell is a registered professional mechanical engineer in both New Mexico and California and a certified state energy auditor in New Mexico. His resume includes: working for Lawrence Berkeley National Laboratory as a staff scientist and senior energy management engineer for more than 20 years; participating on the Technical Committees for Laboratories for the 21st Century and Data Centers for the 21st Century; contracting with the Department of Energy as an principal investigator; teaching at the University of New Mexico and for Labs21; consulting to Sandia Corporation as an energy engineer, as well as providing renewable energy consulting services for various mechanical engineering and architectural projects for more than 35 years.
Mr. Bell is a co-inventor of the Berkeley Hood and is credited with a number of publications, best practice guides, technical bulletins, and magazine articles in his career. He was a principal author of the Design Guide for Energy-Efficient Research Laboratories and is the chief editor of the Labs21 Tool Kit available on CD.
Mr. Bell is currently an energy engineer in the Environmental Energy Technologies Division at Lawrence Berkeley National Laboratory.