The Syracuse/IBM Green Data Center utilizes micro turbines in combination with exhaust fired heat exchangers and absorption chillers to produce electrical power, cooling and heating for the data center and surrounding infrastructure. The overall efficiency of cogeneration systems deperid greatly on the utilization of turbine exhaust heat. This makes a data center (where cooling load and electrical power requirements are closely correlated) an excellent candidate for cogeneration technology. Over 200 data points collected in the data center allow for in-depth energy analysis of this unique data center and the surrounding infrastructure. This paper provides information on the Syracuse/IBM Green Data Center systems as well as analysis of the data center Over all four seasons. In addition to PUE, the common data center metric, a new metric defined as ERE] is used to measure data center efficiency when energy is exported to the surrounding infrastructure.