Utility Billing Definitions

Coincidental Peak is a customer peak that happens during the utility peak.  A coincidental peak might happen at 5 pm during July, when it is very hot outside and air conditioning units are running at full capacity.

Control Period is the set amount of time when curtailment rates will apply.  The control period is designed to reduce the utility peak by controlling the load at the customers that have agreed to an interruptible rate schedule.

Curtailment means reduction of load.  In utility billing, curtailment means reducing the demand, usually during the utility peak period.

Demand is the amount of power being supplied.  This is usually measured in kW (kilowatts).

Interruptible rates require an agreement between the customer and the utility that allows the utility to stop supplying power during an agreed upon time.  This is usually done to allow the utility to shed load during a peak period.  These rate schedules are financially attractive if the customer can have the flexibility to be disconnected with short notice.

Island Generation means that a customer must be disconnected from the utility grid before generating electricity.

Non-Coincidental Peak is a customer peak set when the utility is not in a peak period.  For instance, if you set your peak at midnight or in March, this would not coincide with the utility peak.

Off-Peak is a defined time when the utility demand is low.  Off-peak periods in Arkansas are usually 8 pm until 2 pm the next day, and the months of October thru May.

Peak Period is the time when the utility is experiencing the highest demand.  Daily peak periods in Arkansas are generally 2 pm – 8 pm.  The annual peak period is usually June-September.

Peak Shaving means reducing demand during utility peak periods.

Ride Through Penalty is the extra amount of money that interruptible customers will pay if the utility has to supply energy during the control period.

Synchronized Generation means that a customer can generate electricity (e.g. with diesel generators) while still being connected to the utility grid.

Time of Use rates have different charges for energy based on the time of day that they are consumed.  Energy usage during off-peak times is less expensive than usage during the peak period each day.