The fixed charges are charged by the electricity provider based on the maximum electrical demand of the user. The consumer must limit their electricity consumption to the stipulated maximum demand. This post provides a formula for calculating maximum demand.
1). Overview
The maximum demand is measured by the electrical power provider at pre-defined intervals (for example, every 30 minutes or every 15 minutes) using an energy meter that has been properly sealed and calibrated. Maximum demand is generally expressed in kVA for the billing purposes.
Consumers have to request the maximum demand from their electricity provider, taking into consideration the type of industry and the usage pattern of the equipment.
The consumer is required to pay fixed charges based on the Maximum Demand obtained from the provider, which is the optimum (maximum) rate at which an electrical power has been utilised over any period of the defined sequential minutes in the billing month.
2). Evaluation
The following is a general formula for calculating the Maximum Demand:
Maximum Demand = [Connected Load x Load Factor (LF)] / [Power Factor(PF)]
Where,
Connected Load = Total Connected load in (kW)
Load Factor (LF) = Utility Factor x Diversity Factor
Power Factor (PF) = System average Power Factor
Ex:
In Steel Plant,
Total facility connected load: 6500 kW
Load Factor (LF): 0.4
Power Factor (PF): 0.95
Maximum Demand= (6500 x 0.4) / 0.95 = 2737 kVA
The Time Profile of the Load & Equipment Usage can be used to determine the Utility Factor & Diversity Factor. All of the facility’s equipment may not function at the same time or with full load.
As a result,
Diversity Factor in (%) = Installed Load / Running Load
3). Overall Perceptions
After evaluating the load pattern of electrical installation, the consumer should approve maximum demand. Obtaining a greater Maximum Demand will result in higher (high) minimum fixed charges as well as a higher deposit, and if the sanctioned maximum demand is exceeded, the consumer will face a penalty.