Generator Load Subtracter

Units:	MW
Mode:	Input Only
Multi-band:	False
Default Value:	0
Validation Rule:	Any Value
Key Property:	No
Description:	Generation subtracted from the System load duration curve prior to slicing.

Generator Load Subtracter is capacity subtracted from the system load prior to either slicing of the curve into LDC and then blocks or chronological fitting (depending on the chronology setting of the simulation phase). This applies to MT Schedule and LT Plan. For systems with a significant amount of No Cost Generation Capacity such as solar, wind and other renewables subtracting the profile of this generation off the system load will yield a net load profile that is more accurate for the LDC method.

Note that for simulation the original load is always used. This property only affects the LDC slicing or chronological period fitting/sampling.

The defined amount is by default subtracted from the load regardless of the number of Units installed. However, Load Subtracter Global can be used to control how the value is interpreted for multi-unit generators.

Example

In the following example the Generator represents a renewable source "PV". The 1 MW units are scaled up to the installed capacity via the Escalator shown in Table 2. Likewise the Rating is produced by a Variable in Table 3. The Load Subtracter then has the same Variable applied so that the subtracted capacity matches the Rated Capacity in every period.

Table 1: Generator using Load Subtracter

Property	Value	Units	Band	Action	Variable	Data File	Scenario
Units	1	-	1	×	PV
Max Capacity	1	MW	1
Rating	0	MW	1		PV
Load Subtracter	0	MW	1	×	PV	PV AVG.csv	Load Subtracter

Table 2: Variable Definition

Variable	Property	Value
PV	Index	3000

Table 3: Variable Definition

Variable	Property	Value	Units	Band	Data File
PV	Profile	0	-	1	PV AVG.csv
PV	Error Std Dev	0	%	1	PV STDDEV.csv
PV	Min Value	0	-	1
PV	Max Value	1	-	1
PV	Auto Correlation	70	%	1