Benefits of Enhanced Data Quality and Visualization in a Control System Retrofit

Fredric J. Smothers, F. Smothers & Associates
Kristopher L. Kinney, Engineered Web Information Systems

Keywords

Abstract

This paper discusses a recent innovative control system retrofit built with the aim of providing high-quality data and data visualization tools to the operator with the intent of using the information to improve operation. After eleven months of operation, comparing energy use to the previous four years gives savings estimates of 12% for electricity and 18% for steam use. Occupant comfort has also improved.

This approach to energy management differs from typical systems in that it is not black-box technology. Operators have the ability to use the information provided for finetuning control loops, reset schedules, and commissioning. The system includes high-quality sensors and high-resolution data collection to tighten control and ensure that the operator can fully trust the data he or she sees. The use of non-proprietary devices frees the operators from being tied to specific vendors, and the TCP/IP interface allows for greater freedom for normal, off-hour, and operator relief operations.

Trending and visualization are key. All data points, and most calculated points are trended and archived at up to one-minute intervals. Data visualization tools have been provided to the operator to view real-time and historic data in a manner not typically found in building automation systems. Metrics gauge operation in both text and graphic-based form, including time series and plots formed “on-the-fly”. Trending of control parameters from the existing data files, creates profiles for flexibility and better start-up routines. Other uses of the high-resolution data include decreased system time to turn-over the system to the operators, with more emphasis placed by operators on system commissioning and heat balance of the air, water, and control systems. It also provides the information needed to justify savings opportunities in future equipment upgrades.