Professor Khalifa is examining improving the efficiency of data centers through subzero data center chip cooling. In the research that was primarily supported by NYSERDA, Professor Khalifa is developing a parametric analytical model as well as an hour-by-hour annual energy simulation model of a power and refrigeration cascade system (PARCS) that has the potential to realize the benefits of low-temperature operation of the computer chips while decreasing the overall power consumption of the servers and their conventional cooling infrastructure.