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Objects and Methods : Power Reservoir Methods : User Methods : Power Unit Information
Power Unit Information
This category is used to provide information on unit information when one of two plant level power methods is selected. This category is only available if the Plant Efficiency Curve or Plant Power Coefficient methods are selected.
* None
This is the default, no-action method.
* Plant Power Table with Units
When selected, the Plant Power Table with Units method allows the user to specify the number of units associated with each Turbine Release / Power combination on the Plant Power Table. In addition, at the end of the power method, the Operating Head and Turbine Release are looked up to compute the number of units that are generating.
Slots Specific to This Method
 Plant Power Table
Type: Table Slot
Units: LENGTH, FLOW, POWER, NONE
Description: 3‑D table used to determine power using interpolation
Information: Data must be entered into the table in increasing, concave blocks of the same Operating Head for the three-dimensional table interpolation to work correctly. For every block of the same Operating Head in column 1, Turbine Release should be listed in increasing, concave order in column 2, and the corresponding Power in column 3. The number of units should be increasing in column 4. There should also be a point of zero Turbine Release and zero Power for each operating head. The second to last row for each operating head is the point of best efficiency. The last row for each operating head is the point of maximum Turbine Release and maximum Power production. If there are only two rows for a given operating head, both the best efficiency and max capacity are equal to the second row. The table shown below is an example of the proper way to formulate the Plant Power Table, with units.
 
Operating Head
Turbine Release
Power
Number of Units
30
0
0
0
30
100
100
1
30
200
175
2
40
0
0
0
40
100
125
1
40
220
195
2
50
0
0
0
50
110
147
1
50
250
205
2
I/O: Input Only
 Number of Units Generating
Type: Series
Units: NONE
Description: The number of units generating on this timestep
Information: The value in this slot is computed by looking up the Operating Head and Turbine Release on the Plant Power Table to find the number of units.
Note: This computation is a 3‑D interpolation on the Plant Power Table so there can be a fractional number of units generating; for example, 1.7.
I/O: Output Only
Revised: 07/09/2023