Energy Use During a Working Day

A managed PC can assume several power states during a work day. Common power states include active power, idle power and Standby. Each of the power states must be included in a methodology designed to emulate the way people actually use their computers during the course of a workday. This graphic demonstrates the typical distribution of power draw levels during the workday modeled by our proposed methodology:

System power-draw levels during a 9-hour workday. The percentages shown here are the power level amount above the idle power level as compared to the idle power level. Intel® Core™ 2 Duo processor E4300 on the Intel® 965 chipset. See final page for system configuration details. Performance tests and ratings are measured using specific computer systems and/or components. Actual results may vary.

Each piece of this pie-chart represents the amount of time spent at a given system power-draw level. The percentages are the power level amount above the idle power level as compared to the idle power level. The main observation here is that over 35% of the time during the nine-hour working day—about three hours and 13 minutes—the system is at an idle power draw level or at Standby in this proposed methodology. More important however, is that all system power draw characteristics – active, idle, and Standby – are in the context of a reasonable usage model.

At the end of the day’s activities, the system is put to Standby for 15 hours, until it is awoken to start the next day. Accounting for this Standby time, the breakdown of system power draw levels looks like this:

System power-draw levels during 24 hours. The percentages shown here are the power level amount above the idle power level as compared to the idle power level. Intel® Core™ 2 Duo processor E4300 on the Intel® 965 chipset. Performance tests and ratings are measured using specific computer systems and/or components. Actual results may vary. See final page for system configuration details.