NSIDC green data center project: Coolerado and modeling an application of the Maisotsenko cycle

The National Snow and Ice Data Center recently replaced its traditional cooling system with a new air conditioning system that utilizes an economizer and Coolerado air conditioning units. These units represent one of the first commercially available applications of the Maisotsenko cooling cycle. A datalogging system was installed that measured the data center’s power consumption before and after the cooling system was replaced. This data was organized and used to prove a 90% cooling energy reduction for the NSIDC. The data logging system also collected temperatures and humidities of inlet and outlet air of a Coolerado air conditioner. After using these data to validate a theoretical model developed by researchers at the National Renewable Energy Laboratory, the model was used to simulate slightly modified heat and mass exchanger designs of the Coolerado system to improve performance. Sensitivity analysis was performed and found a few design parameters that are important to the thermodynamic performance of the Coolerado system, while others were proved insignificant. Channel heights, sheet size and ambient pressure have the most significant impacts on the performance. Overall, it was found that the current design performs reasonably well and with minor modifications could perform optimally, as suggested by the theoretical model. DEDICATION This Thesis Report is dedicated to my parents, Richard and Jeri. While they may not understand much of my college academic work, they’ve been fully supportive for the past 17 years of my educational career, which culminates with the submission of this Thesis. It is also dedicated to all of the building engineers in industry, who are striving to make a difference in the built environment where so many other outside factors make or break a project’s success, often for reasons completely unrelated to the pursuit of the perfect engineering solution.