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Objects and Methods : Thermal : User Methods : Thermal Unit Replacement Value
Thermal Unit Replacement Value
* None
No evaluation is made.
* Calculate Thermal Unit Replacement Value
This method applies a time dependent piecewise linear value to power generated. The value is based on replacing thermal units. The order of power source evaluation matters for simulation because it is nonlinear; the order affects the credit given to each power source. Evaluation before other power sources will result in higher credit. The optimization doesn’t allocate credit to individual power sources, and the order has no effect on it.
At the end of the run, the economic value of hydropower is calculated based on the savings from replacing generation from thermal power sources. The first part of the calculation is to assign thermal power sources to meet a load based on their average cost of operation. The second part of the calculation is to use hydropower to back down generation from the least efficient units that were used to meet the load in the initial calculation.
This method is dependent on having Hourly Load method selected. See Hourly Load for details.
Slots Specific to This Method
 Thermal Unit Cost
Type: Agg Series Slot
Units: PowerCost
Description: The cost of generating at each unit.
Information: The columns represent the thermal units.
I/O: Input
 Thermal Unit Capacity
Type: Table Slot
Units: Power
Description: Size of the units used to value hydropower.
Information:  
I/O: Input
 Thermal Unit Availability
Type: Agg Series Slot
Units: No units
Description: Availability of each unit for each time period.
Information: A fraction ranging from 0 to 1.
I/O: Input
 Thermal Energy
Type: Agg Series Slot
Units: Energy
Description: Energy generated by each unit in order to meet the load.
Information: One column for each unit.
I/O: Output
 Thermal Power Source Evaluation Order
Type: Table Slot
Units: None
Description: One row for each power source and one column with a unique positive value for power sources to be used.
Information: NaN indicates the power source doesn’t apply or has already been included in economic calculations.
I/O: Input
 Thermal Marginal Operating Cost
Type: Series Slot
Units: PowerCost
Description: Additional marginal value of an extra unit of hydropower.
Information:  
I/O: Output
 Thermal Previous Marginal Operating Cost
Type: Series Slot
Units: PowerCost
Description: Additional marginal value of the previous unit of unit of hydropower generated.
Information: This value will be the same as the Thermal Marginal Operating Cost if hydrogeneration is in the middle of a unit. However, the hydro generation for some time periods may exactly match the full use of some number of units. This is particularly likely for optimization models. In these cases the marginal operating cost and the previous marginal operating cost will differ because they represent different units.
I/O: Output
 Thermal Tolerance
Type: Scalar Slot
Units: Power
Description: Tolerance for considering a solution to have hydrogeneration exactly equal to some number of units.
Information: Floating point arithmetic usually requires a tolerance for comparing numbers. In this case, if the values are equal within the tolerance, then the Thermal Previous Marginal Operating Cost will have a different value than the Thermal Marginal Operating Cost.
I/O: Input
 Thermal Only Cost
Type: Series Slot
Units: PowerCost
Description: Cost of meeting the loads with only thermal units and no hydropower.
Information: One column. One row for each slot, as follows:
Conventional Hydro Power
Pump Power Evaluated
Allocated Energy Evaluated
Conventional Total Avoided Cost
Pump Total Avoided Cost
Allocated Total Avoided Cost
Total Avoided Operating Cost All
Regulation Value
Reg. Operating Cost
Total Future Value of Used Energy
Total Spill Cost
Cumul Stor Value
Net Total Avoided Cost
Objective
I/O: Output
 Thermal Conventional Replacement Value
Type: Series Slot
Units: None
Description: Calculated value of conventional hydropower using thermal evaluation.
Information:  
I/O: Output
 Thermal Pump Replacement Value
Type: Series Slot
Units: Value
Description: Calculated value of net hydropower generated by pumps using thermal evaluation.
Information:  
I/O: Output
 Thermal Allocated Replacement Value
Type: Series Slot
Units: Value
Description: Calculated value of allocated hydropower using thermal evaluation.
Information:  
I/O: Output
 Thermal Avoided Operating Cost
Type: Series Slot
Units: Value
Description: Combined value of conventional, pump, and allocated hydropower using thermal evaluation.
Information:  
I/O: Output
 Thermal Net Avoided Cost
Type: Series Slot
Units: Value
Description: Thermal Avoided Operating Cost minus the value of water used for spill or generation.
Information:  
I/O: Output
 Thermal Total Values
Type: Table Slot
Units: None
Description: Sum over time for several slots used in the thermal economic evaluation.
Information: One row for each slot. One column.
I/O: Output
 Allocated Minimum
Type: Agg Series Slot
Units: Power
Description: Minimum power generation for projects with allocated energy.
Information: One column for each project to be allocated.
I/O: Input
 Allocated Maximum
Type: Agg Series Slot
Units: Power
Description: Maximum power generation for projects with allocated energy.
Information: One column for each project to be allocated.
I/O: Input
 Allocated Total Energy
Type: Agg Series Slot
Units: Energy
Description: Total energy to be allocated from a project over some time period.
Information: One column for each project to be allocated. Totals should be entered with some consistent period. For example, values entered only once a day will be allocated across that day assuming the model has a timestep smaller than one day.
I/O: Input
 Allocated Detail Energy
Type: Agg Series Slot
Units: Energy
Description: Result of allocating the energy to individual time periods.
Information: One column for each project to be allocated.
I/O: Output
 Allocated Energy Sum
Type: Series Slot
Units: Energy
Description: Sum of allocated energy across projects.
Information: Only used in optimization to assist in mathematical representation.
I/O: Output
 
Revised: 07/17/2020