Extrapolation

In order to determine the expected consumption or the expected performance for a register on a specific date, you need data on the metering patterns of the register.

You can take this information from previous meter reading results, from a predefined periodic consumption value or from a predefined period demand.

The base period from which the expected values are calculated is very important during extrapolation. The period in which bases are created to determine expected values during extrapolation are included in the base period. Using the base period category field in the installation, you can control whether to extrapolate the expected values based on the previous period or the period of the previous year.

Meter reading results are the ideal base from which to determine expected values, as these results best reflect the consumption patterns of the customer. In order to use meter reading results, you must ensure that the base period (the interval between the first and the last meter reading result) used for extrapolation is representative.

You can only extrapolate from a previous period, if it is representative. Whether a period is representative or not is a result of the original weighting procedure.

Determining Whether a Period is Representative

To determine whether a base period is representative, use the following information:

Weighting portion of period = Minimum portion

or

Minimum portion in percent * Length of meter reading period

= Minimum length of base period

Example

Weighting portion of period = Minimum portion

or

Minimum portion in percent (50%) * Length of meter reading period (365 days)

= Minimum length of base period (182.5 days)

In the example, the base period must have a minimum weighting portion of 50% or be at least 182.5 days long in order to be representative.

( )

The period from P to Y is not representative because it does not have the minimum weighting portion (only 20% rather than the required 50%). This means that this period alone cannot be used as a basis for extrapolation. The system goes back to the previous reading (I). The period from P to I is representative because it has a weighting portion of 20% + 60% = 80%. The period from P to I can be used as a basis for extrapolation.

Meter Reading Results or Period Value as a Basis for Extrapolation

The system determines whether to use meter reading results or a selected period value as a basis for extrapolation in the following way:

Based on the last correct meter reading results, the system goes back to the previous reading and runs through the following process:

( )

If you enter a modified periodic consumption in transaction Maintain Periodic Consumption (EL 56) for a point in time that lies within the base period for the next extrapolation, the system will inform you that the entered periodic consumption can influence the extrapolation results.

Determination of Expected Consumption for Consumption Registers

Determination of the expected consumption based on the meter reading results

Determination of the expected consumption based on the period consumption

The following reasons can result in the period consumption being used as a basis for extrapolation:

The expected consumption is determined in the following way:

Determination of the Expected Demand for Demand Registers

Determining the expected demand for demand registers is a similar process to determining the expected consumption for consumption registers. Demand per unit of weight is, however, not calculated. In this case, you must determine the highest demand for the base period.

Determination of the expected demand based on the meter reading results

Determination of the expected demand based on the period demand

The following reasons can result in the period demand being used as a basis for extrapolation:

The expected demand is determined in the following way: