Planning the information technology (IT) installation in a data processing environment is a cumbersome task. Even though Thermal Guidelines for Data Processing Environments (ASHRAE 2004) addresses heat load planning, the electrical and thermal considerations go hand-in-hand. Using the correct electrical planning values can make the difference between either having adequate capacity or running out of finite power. The question becomes, what is correct? This paper will examine terms like nameplate and power consumption with an explanation of how each term should be applied in the data processing environment. In addition, a minimum set of electrical and thermal specifications are introduced. Finally, strategies are provided on how to properly plan the electrical environment in tandem with the thermal environment for maximum energy efficiency.