In
telecommunication
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...
,
electronics
The field of electronics is a branch of physics and electrical engineering that deals with the emission, behaviour and effects of electrons using electronic devices. Electronics uses active devices to control electron flow by amplification ...
and the
electrical power industry
Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by ...
, the term demand factor is used to refer to the fractional amount of some quantity being used relative to the maximum amount that could be used by the same system. The demand factor is always less than or equal to one. As the amount of demand is a time dependent quantity so is the demand factor.
:
The demand factor is often implicitly averaged over time when the time period of demand is understood by the context.
Electrical engineering
In
electrical engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
the demand factor is taken as a time independent quantity where the numerator is taken as the maximum demand in the specified time period instead of the averaged or instantaneous demand.
:
This is the peak in the
load profile
In electrical engineering, a load profile is a graph of the variation in the electrical load versus time. A load profile will vary according to customer type (typical examples include residential, commercial and industrial), temperature and holi ...
divided by the full load of the device.
Example:
If a residence has equipment which could draw 6,000 W when all equipment was drawing a full load, drew a maximum of 3,000 W in a specified time, then the demand factor = 3,000 W / 6,000 W = 0.5
This quantity is relevant when trying to establish the amount of load for which a system should be rated. In the above example, it would be unlikely that the system would be rated to 6,000 W, even though there may be a slight possibility that this amount of power can be drawn. This is closely related to the
load factor which is the average load divided by the peak load in a specified time period.
:
See also
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Capacity factor
The net capacity factor is the unitless ratio of actual electrical energy output over a given period of time to the theoretical maximum electrical energy output over that period. The theoretical maximum energy output of a given installation is def ...
*
List of energy storage projects
This is a list of energy storage power plants worldwide, other than pumped hydro storage.
Many individual energy storage plants augment electrical grids by capturing excess electrical energy during periods of low demand and storing it in oth ...
*
Load factor (electrical)
In electrical engineering the load factor is defined as the average load divided by the peak load in a specified time period. It is a measure of the utilization rate, or efficiency of electrical energy usage; a high load factor indicates that loa ...
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Diversity factor
In the context of electricity, the diversity factor is the ratio of the sum of the individual non-coincident maximum loads of various subdivisions of the system to the maximum demand of the complete system.
: f_\text = \frac
The diversity factor ...
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Utilization factor
The utilization factor or use factor is the ratio of the time that a piece of equipment is in use to the total time that it could be in use. It is often averaged over time in the definition such that the ratio becomes the amount of energy used d ...
References
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{{Electricity generation
Power engineering