“Energy and Water Efficiency Improvements for Dishrooms in Military Dining Facilities” by Dr. Frank Johnson
Energy and water usage for commercial food service have a significant impact on the overall usage of a facility. Daily meal preparation and cleanup in a military dining facility (DFAC) represents more than 75% of the energy and water load. Within the food service facility itself, the dishwashing room or “dishroom” has the highest energy intensity compared to the other zones within a DFAC. This project identified and demonstrated dish machine with waste water heat recovery to reduce the energy and water usage and intensity within a dishroom used for cleaning and sanitizing flatware, dishes, cooking vessels and other food service-related utensils at a military installation. Results showed a savings of 35 therms per day of natural gas and 6,375 gallons of water per day when replacing the existing machine with an energy efficient design. These savings equate to 12,775 therms and 2.33 million gallons of water per year.
“Hygroscopic Cooling Tower for Reduced Heating, Ventilation, and Air Cooling Water Consumption” by Dr. Christopher Martin
This project evaluated technology for water use reduction at Department of Defense (DoD) facilities that use cooling towers for building comfort control, cold storage and data center cooling. Since they approach the ambient wet bulb temperature, cooling towers allow chillers and other equipment to maintain operating efficiency, even during periods with a high dry bulb temperature. However, cooling towers are intense consumers of water and are a key target for water conservation improvements. Hygroscopic cooling is an advanced cooling tower concept intended to optimize water use without significant degradation of cooling performance. With this system, 100% of the makeup water is evaporated for cooling; no water is wasted in a blowdown stream. Additionally, when ambient dry bulb temperatures are cool enough, water evaporation in the hygroscopic system is restricted to increase the proportion of dry sensible cooling. This technology was demonstrated at two DoD facilities with contrasting climates to determine its range of water saving potential. The presentation discussed hygroscopic cooling within the context of conventional wet cooling towers and existing water saving techniques together with demonstration updates from the two DoD facilities.
is a research and development manager with the Energy Delivery and Utilization Group at the Gas Technology Institute (GTI) in Des Plaines, Illinois. Since 1998, his work has focused on residential/commercial appliance development and testing, receiving four patents. He has managed and/or served as a principal investigator on several projects that resulted in a new appliance being developed, field tested and brought to market. He has also conducted research in the areas of fuel interchangeability, low nitrogen oxide burner development, water heating and space conditioning. Dr. Johnson has been active with professional societies including the North American Foodservice Equipment Manufacturers (NAFEM), American Society of Testing and Materials (ASTM), Gas Foodservice Equipment Network (GFEN), American Society of Agricultural Engineers (ASAE), American Society of Heating, Refrigeration, Air-Conditioning Engineers (ASHRAE), American Society of Mechanical Engineers (ASME), American Institute of Chemical Engineers (AiChE), and American Physical Society (APS). He received his Ph.D. in mechanical engineering from Northwestern University, his master’s degree in mechanical engineering from the University of Illinois, Champaign-Urbana, and a bachelor’s degree in mechanical engineering from the University of Kentucky, Lexington.
Dr. Christopher Martin is a Senior Research Engineer at the Energy and Environmental Research Center, a non-profit, applied research laboratory at the University of North Dakota in Grand Forks. Dr. Martin’s principal areas of expertise include thermal energy conversion, utilization and system analysis; mitigation of environmental effects from power generation, including air emissions from combustion and gasification systems; and, minimizing water use within energy conversion processes. Dr. Martin has been a principal investigator for previous United States Department of Energy research projects into the hygroscopic cooling concept. He earned a bachelor’s degree in mechanical engineering from the University of North Carolina at Charlotte, and received master’s and doctoral degrees in mechanical engineering from the University of Florida in Gainesville.