Load curve
A picture of how electricity demand changes over time.
An illustrative daily load profile. The shape is conceptual; no site or measured day is represented.
A load curve plots electrical power demand against time. It shows how demand changes through a day or another period. This time profile is different from an economic demand curve, which relates demand to price.
Putting demand on a time axis
A load curve plots electrical power demand against chronological time. Its shape can reveal morning ramps, evening peaks, or seasonal patterns. It is not the price-versus-quantity curve used in economics, or a load-duration curve that sorts demand from highest to lowest.
The area beneath a power-versus-time curve represents energy. The highest point shows peak demand, while the steepness of a change indicates how quickly demand is rising or falling. Always read the axes and measurement interval.
Why it matters
The shape of demand matters alongside its total. Two days can use the same energy while placing different demands on equipment and resources.