The measurement of maximum demand and the determination of load factor

SINCE Hopkinson in 1892 first suggested the idea that the distribution of a customer´s load throughout the day should have some bearing upon the amount which that customer should pay to the Central Station for his power, the subject of demand and load-factor measurement in its various aspects has been many times discussed. In the determinination of watts, amperes or any similar electrical quantity we have definite units upon which to base our measurements, and there is little room for controversy. But, when the quantity “demand”, being a more or less mathematical concept, embodying the combination of electrical units with time in a rather indefinite way, comes under consideration, very divergent views as to its nature, measurement and true significance may be and have been expressed.