| Units: | - |
| Mode: | Input Only |
| Multi-band: | False |
| Default Value: | 0 |
| Validation Rule: | In (0,1) |
| Key Property: | No |
| Description: | Maximum number of units automatically retired in aggregate over the planning horizon |
Line Max Units Retired is the maximum number of units automatically retired in aggregate over the planning horizon by LT Plan. The cost of retiring a unit is given by Retirement Cost. Obviously the unit(s) must exist at some time in the planning horizon for there to be retirements. Thus you must define either Units or Max Units Built.
Example
| Line | Property | Value | Units |
|---|---|---|---|
| Old HVDC | Units | 1 | - |
| Old HVDC | Max Capacity | 500 | MW |
| Old HVDC | FO&M Charge | 2000 | $000 |
| Old HVDC | Max Units Retired | 1 | - |
| Old HVDC | Retirement Cost | 1000 | $000 |
Max Units Retired can also be used to retire a stage of a multi-stage transmission project as in the following example:
Example
| Line | Property | Value | Units |
|---|---|---|---|
| HVDC Stage 1 | Units | 0 | - |
| HVDC Stage 1 | Max Flow | 700 | MW |
| HVDC Stage 1 | Max Units Built | 1 | - |
| HVDC Stage 1 | Build Cost | 25000 | $000 |
| HVDC Stage 1 | Economic Life | 35 | years |
| HVDC Stage 1 | WACC | 8 | % |
| HVDC Stage 1 | Max Units Retired | 1 | - |
| HVDC Stage 2 | Units | 0 | - |
| HVDC Stage 2 | Max Capacity | 1000 | MW |
| HVDC Stage 2 | Max Units Built | 1 | - |
| HVDC Stage 2 | Build Cost | 15000 | $/kW |
| HVDC Stage 2 | Economic Life | 35 | years |
| HVDC Stage 2 | WACC | 8 | % |
Here the Line "HVDC Stage 1" represents the first stage of a HVDC project. "HVDC Stage 2" is the second stage when capacity is upgraded. The two Lines build and retire decisions must be linked logically by Constraints using the coefficients Units Built Coefficient, Units Retired Coefficient, Units Built in Year Coefficient, and Units Retired in Year Coefficient as described in the LT Plan topic.
See also: