Strategies for energy benchmarking in cleanrooms and laboratory-type facilities

Buildings with cleanrooms and laboratories are growing in terms of total floor area and energy intensity. This building type is common in institutions such as universities and in many industries such as microelectronics and biotechnology. These buildings, with high ventilation rates and special environmental considerations, consume from 4 to 100 times more energy per square foot than conventional commercial buildings. Owners and operators of such facilities know they are expensive to operate, but have little way of knowing if their facilities are efficient or inefficient. A simple comparison of energy consumption per square foot is of little value. A growing interest in benchmarking is also fueled by: A new U.S. Executive Order removing the exemption of federal laboratories from energy efficiency goals, setting a 25% savings target, and calling for baseline guidance to measure progress; A new U.S. EPA and U.S. DOE initiative, Laboratories for the 21st Century, establishing voluntary performance goals and criteria for recognition; and A new PG and E market transformation program to improve energy efficiency in high tech facilities, including a cleanroom energy use benchmarking project. This paper identifies the unique issues associated with benchmarking energy use in high-tech facilities. Specific options discussed include statistical comparisons, point-based rating systems, model-based techniques, and hierarchical end-use and performance-metrics evaluations