Conventional models for estimating electrical efficiency of data centers are grossly inaccurate for real-world installations. Electr icity usage costs have become an increasing fraction of the total cost of ownership (TCO) for data centers. It is possible to d ramat ically reduce the electrical consumption of typical data centers through appropriate design of the physical infrastructure a nd IT ar chitecture. This course explains how to quantify the electricity savings and provides examples of methods that can greatl y reduce el ectrical power consumption.