Advantage was recently challenged to provide a new energy efficient process cooling system for a plastics company located in Minnesota. The company’s existing cooling system was both under capacity and aging and was becoming unreliable. Upon evaluating the process needs, it was determined that while the company was currently using all chilled water to provide cooling, about 35% of the cooling load did not require chilled water and could be cooled with water as high as 90F.
Advantage application specialists working closely with the company and local Advantage sales representative soon came up with a unique system to both increase the cooling capacity of the system and to take advantage of the cool Minnesota climate. Two discreet systems were installed.
The main cooling system was an outdoor air-cooled chiller with integral reservoir and pumping system sized to provide enough cooling capacity for the entire cooling load. For operation during the winter, a dry cooler system was installed to support the material processing load. This system automatically engages when the ambient temperature is below the warm return from process fluid temperature. The dry cooling system uses ambient air rather than mechanical refrigeration to provide the required cooling, drastically reducing energy use and wear and tear on the chiller system.
In addition to the outdoor chiller and fluid cooler system for the material processing load a second dry cooler system was installed to provide 85F fluid to the 35% of the load that could accept higher fluid temperatures. This system automatically engages when the ambient temperatre is 65F or below which was estimated to be more than 55% of the year in Minnesotat. This load was previously cooled year round by mechanical refrigeration.
The dry cooler system also addressed another concern raised by the company, water quality. While an evaportive cooling tower system would have made a good solution for this project the company was very concerned with water quality management and wanted a closed loop system that would not have the issues typically associated with cooling tower systems. The fluid cooler system fully addressed this concern.
After documenting the projected savings and submitting it to the local utility an energy rebate of about 23% of the project equipment cost was granted. The rebate was a nice bonus to the ongoing energy savings of the system design.
Overall the project met the customers goals of increased cooling capacity which increased product output while saving energy compared to the old system.