IEA Standby Power Initiative

Conclusion of Task Force 1: Definitions and Terminology of Standby Power

The present document has been developed and approved by the participants of Task Force 1 during a two-day meeting on 17 & 18 November 1999 in Washington DC.


The IEA is committed to encouraging improvement in the energy efficiency of products in a manner that does not impede product performance, safety, overall value, or customer satisfaction. Accordingly, in January 1999 the IEA initiated an international collaboration to address the growing concern of the energy consumed in the standby mode of numerous electrical products. It was recognized that successful collaboration would need a widely accepted definition of "standby power", which did not exist at the time. A Task Force, consisting of representatives from industry, government, and technical bodies, was created to develop definitions that would allow further action by the IEA and other entities. Furthermore, the scope, name and measurement methods were to be developed.

Members of the Task Force recognized early on that no definition would satisfy everyone. To this end, the Task Force agreed that the principal goal was to create a "common language" in order to discuss standby power. The Task Force also agreed that the definition need not be technically rigorous and need not cover 100% of the situations, but should be comprehensive enough for subsequent policy discussions.

As a result of extended discussions, the Task Force developed the following definition of standby power, along with clarifying remarks and observations.


Standby power use depends on the product being analyzed. At a minimum, standby power includes power used while the product is performing no function. For many products, standby power is the lowest power used while performing at least one function.

This definition covers electrical products that are typically connected to the mains all of the time.

Based on this definition, certain types of products generally do not have standby power consumption. This includes, for example, products that have only two distinct conditions: "on" and "off", where the product does not consume power when it is off.

The left figure illustrates the power levels of the "on" and "off" conditions for products that do not have standby power consumption. The figure on the right illustrates the relationship between standby power consumption and the power consumption of other product conditions.

Left: power levels of the 'on' and 'off' conditions for products that do not have standby power consumption. Right: the relationship between standby power consumption and the power consumption of other product conditions.

Left: No standby power consumption and other product conditions.

Right: Conditions of products with relationship between standby.


  1. There already exist energy efficiency programs that address standby in various product categories. The Task Force does not intend this definition to supersedes or replaces the definition underlying such programs.
  2. Standby power consumption should be viewed from the context of the overall efficiency and performance of the product.
  3. Specific measurement procedures should be determined by the appropriate standardization bodies. It is recommended that these bodies consider the role of power factor and power management, and choose a suitable measurement interval.
  4. For electrical products, standby power and standby energy consumption are generally expressed in average Watts and kilowatt-hours, respectively.
  5. The Task Force discussed the most appropriate word for "standby" energy consumption. The underlying problem is that this energy consumption covers several different product conditions. In the end, the Task Force used "standby power"; however, the appropriate technical bodies may choose to develop more precise terms that are consistent with the definition and test procedures used.
  6. The phrase "no function" given in the definition of standby includes the situation in which the secondary load is disconnected from the power supply. This is often called the "no load" power use.

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