Evaluation of Chiller Plant Energy Conservation Opportunities at Fort Hood, Texas

Chiller plant owning and operating costs represent substantial investments at Fort Hood, Texas. Primary objectives of this work are to evaluate the performance of major plants and associated distribution systems, and to identify relevant energy conservation opportunities (ECOs). Significant effort was expended to gather information and document the performance of plant cooling equipment. Data were obtained from site surveys, discussions with vendors and manufacturers, and reviews of previous studies. Performance was documented with field measurements. Subsequent analyses of ECOs were performed with simplified bin methods consistent with first-order conclusions and recommendations required from this work. Results for all ECOs were heavily influenced by the utility rate structure. At Fort Hood, 75 percent of annual chiller energy cost is determined by demand charges. Alternatives for chiller ECOs were also limited by the effects of recent regulations that govern the use of refrigerants. Therefore, realistic improvements that reduce chiller energy consumption necessarily involve replacement or major upgrade of most chillers. Other potential ECOs targeted reductions in chiller and pump energy by modulating speed in relation to cooling load. A select group of chillers will benefit from this technology. The higher capital costs combined with the unusually low energy charge preclude speed modulation for all other motors.