[1] This term generally excludes building energy that is attributed to major end uses (HVAC, lighting, water heating, etc.
[7] Office equipment and other plug loads emit heat which may require the building to supply additional cooling, a side-effect which contributes to total energy consumption.
In general, although total plug load energy use is increasing, the actual plug load equipment stock is getting more efficient; technical advances such as low power consumption by LCD monitors, more effective sleep modes and the uptake of the notebook laptop computer in lieu of a desktop computer have produced lower plug load power levels.
[9] Although the efficiency of this equipment category is improving, many studies have indicated that user behavior may be a factor for its overall increasing energy use.
[10] Additionally, equipment power management adds some uncertainty to estimating plug load energy use.