Energy Performance Analysis of a Combined Cooling Heating and Power System for a Data Center

Abstract

Data centers play an important role in modern business. They require a large amount of electricity and cooling energy simultaneously. In 2007, the percentage of total energy consumed by data centers in total US energy doubled over seven years and it is estimated to be double again by 2012. Currently data centers typically employ separate cooling, heating and power (SCHP) systems. The Combined Cooling Heating and Power (CCHP) system is an efficient, clean, and reliable approach to generating power and thermal energy from a single fuel source simultaneously on site. They could be suitable energy supply systems for data centers since demands from data centers match with the energy generation of the CCHP systems. This paper assesses the energy performance of a CCHP system for the Qualcomm data center in San Diego, California, by means of modeling and operational data analysis. The CCHP system mainly consists of four gas turbines, one exhaust fired absorption chiller, three hot water fired absorption chillers, three electrical chillers and seven cooling towers. System performance models have been developed and validated by experimental data in TRNSYS. The modeling result shows that the CCHP system is capable of meeting the electricity and cooling demands with an overall system efficiency of 46%. As a result, the CCHP system could approximately save 12.9GWh of energy per year compared with SCHP systems. Therefore, the CCHP system is a sustainable and green option for data centers.