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Thermal
Objects and Methods
Thermal
This object models the economics of power generation. One methods evaluates hydro generation by directly replacing power generated by thermal power plants such as nuclear, coal, or gas powered plants and examines the economic savings at the thermal plants. This is the origin of the thermal name for this object. Another method place a piecewise linear or block value on hydropower generation. Typically, the user calculates these block values based on replaced thermal generation or power purchase opportunities, but the source doesn’t matter for the RiverWare model. A third method places a linear value on hydropower generation.
The thermal object is intended to be a singleton (i.e. one thermal object per model), including all of the relevant economic information and linked to all of the power reservoirs. The thermal object provides an economic evaluation for the entire RiverWare model. In addition to economic evaluation, the thermal object is a useful place to summarize the power data of a model. The thermal object has many power related multislots and each multislot can be linked to the individual power related slots on the power reservoirs in a model. Figure 27.1 shows a red thermal object linked to power reservoirs. Like all links, these links may be hidden, dotted, or displayed in a different way to change the relative emphasis of the links in the model. See “Display Groups” in User Interface for details on link groups.
Figure 27.1   
These linked multislots then provide the system totals for these power attributes. Some of the power attributes that may be linked include hydro generation, hydro capacity, pumping generation pumping capacity, and energy in storage. See the full list of multislots below for more detail.
A thermal object may be used with any of the controllers: Simulation, Rulebased Simulation, or RPL-based Optimization.
In a simulation or rule-based simulation model, a thermal object provides an economic evaluation of a solution, but does not influence the solution. An important difference with many other object classes is that the only calculations performed during the timesteps of a run are the multislot totals. All of the economic calculations are performed at the end of the run, after simulation has set all of the other slot values. One consequence of this is that the economic calculations cannot be used to drive a simulation model.
The thermal object is used in most optimization models, because economics is usually a factor in these models. Unlike simulation, in optimization the thermal object can influence the solution. In addition to allowing a modeler to maximize the economic value of hydropower, the thermal object allows a modeler to write constraints and objectives on the power related multislots. For example, total system hydropower generation or capacity can be maximized or constrained to meet a minimum level.
General Slots
Energy In Storage
Type: MultiSlot
Units: ENERGY
Description: The sum of the energy stored in the linked reservoirs.
Information:  
I/O: Output
Hydro Capacity
Type: MultiSlot
Units: POWER
Description: The sum of the power generated by the linked reservoirs.
Information:  
I/O: Output
Hydro Generation
Type: MultiSlot
Units: ENERGY
Description: The sum of the energy generated by the linked reservoirs.
Information:  
I/O: Output
Objective Values
Type: Table Slot
Units: NONE
Description: The optimal objective function values from the last optimization run.
Information:  
I/O: Output
Pumped Storage Generation
Type: MultiSlot
Units: ENERGY
Description: The sum of the energy generated by the linked pumped storage reservoirs.
Information:  
I/O: Output
Pumped Storage Generation Capacity
Type: MultiSlot
Units: POWER
Description: The sum of the power generated by the linked pumped storage reservoirs.
Information:  
I/O: Output
Pumped Storage Pumping
Type: MultiSlot
Units: ENERGY
Description: The sum of the energy consumed by the linked pumped storage reservoirs.
Information:  
I/O: Output
Pumped Storage Pumping Capacity
Type: MultiSlot
Units: POWER
Description: The sum of the power consumed by the linked pumped storage reservoirs.
Information:  
I/O: Output
Ramping Cost
Type: MultiSlot
Units: $
Description: The sum of the ramping cost at the linked reservoirs.
Information:  
I/O: Output
Turbine Decrease
Type: MultiSlot
Units: Flow
Description: The sum of the turbine decrease at the linked reservoirs.
Information:  
I/O: Output
Turbine Increase
Type: MultiSlot
Units: Flow
Description: The sum of the turbine increase at the linked reservoirs.
Information:  
I/O: Output
System Startup Cost
Type: MultiSlot
Units: Value ($)
Description: Total startup cost of all linked reservoirs.
Information: This slot is used to link the Thermal object to each reservoir’s Plant Startup Cost slot.
I/O: Output Only
User Methods
Load
These methods determine if hourly power load data should be part of the economic valuation of hydropower.
* None
This default method does not use hourly power load data.
* Hourly Load
This method calculates the load for each time step as the sum of hourly system load and load adjustment values that are input prior to the beginning of the run.
The Thermal methods use this data for calculating the economic value of hydropower. The Block Hydro methods do not use this data.
Slots Specific to This Method
Load Adjustment
Type: Series Slot
Units: power
Description: Correction to the specified system load, frequently NaN.
Information:  
I/O: Input only
System Load
Type: Series Slot
Units: power
Description: The combined load to be met by both thermal power sources and hydropower.
Information:  
I/O: Input only
Modified Load
This category allows the user to define load leveling on the thermal object. The category is dependent on selecting the Hourly Load method from the Load category. See “Hourly Load” and “Load” for details.
* None
This is the default no-action method.
* Calculate Modified Load
This method takes the System Load (original, unmodified load) and then subtracts the net generation from hydropower to get the Modified Load. It also adds slots to define load leveling in the thermal object. With the new slots, users can write policies that will level the load to the extent possible.
Slots Specific to This Method
Modified Load
Type: Series Slot
Units: Energy
Description: The remaining load after hydropower is generated.
Information: The remaining load equals the original load minus the net generation from the hydropower sources selected in the Modified Load Power Sources Used table. See “Modified Load Power Sources Used”.
I/O: Output
Modified Load Power Sources Used
Type: Table Slot
Units: None
Description: One row for each power source and one column with a positive value for power sources to be used.
Information: NaN indicates the power source doesn’t apply or has already been included in reducing the load.
I/O: Input only
Method Details
Like all thermal method calculations, the method is called at the end of a simulation run. This method first calculates the original, unmodified load (as an energy) by adding the hourly system load and load adjustment slots for all hours within a time step.
The user selects the power sources that will be used to modify the load by setting values in the Modified Load Power Sources Used table. This table has one column and three rows: Conventional Hydro Power Evaluated, Pump Power Evaluated, and Allocated Energy Evaluated. Power sources that should be used to modify the load have a non-NaN value while unused sources have a NaN value. See “Modified Load Power Sources Used” for details.
The Modified Load initially equals the original load (System Load minus Load Adjustment). The net generation from the selected power sources are subtracted from this load. If any of the selected power sources have a value of NaN then the modified load is also NaN. For example, during a normal pre-optimization simulation, modified load will be NaN for all timesteps because hydropower generation is not yet known. In contrast, during a fully specified simulation or a post-optimization rulebased simulation, modified load will be calculated because all hydropower generations will be known. See “Modified Load” for details.
Allocated power is constrained by minimal and maximal power generation for each time period combined with periodic total energy requirements. The power is allocated to level the load in coordination with other power sources.
After calculating the individual economic components for each time period, the totals for all time periods are placed in the Linear Total Values table slot.
See “Calculate Modified Load” in Optimization for details on how the method is used in optimization.
Preferred Customer
A group of reservoirs may be obligated to meet the power demands of preferred customers before this energy is used for other purposes. For example, if a group of reservoirs is owned by another entity, the energy demand of their customers must be met before the energy is coordinated with the other reservoirs in an economic objective, and in this sense, their customers are preferred. In such a situation, some (and perhaps all) of these reservoirs are also treated as allocated energy that can be flexibly used in coordination with the remaining reservoirs.
The methods in this category model the energy needs of the preferred customers. The preferred customers are identified by membership in a Preferred Customer subbasin. This is a predefined type of subbasin.
Note:  Although still shown in the interface, this category no longer has methods that do anything.
* None
Preferred customers are not used in the economic valuation.
* Preferred Customer
In simulation, the Preferred Customer Energy slot holds the amount of energy that should be sent to the preferred customers. This energy is subtracted from the allocated energy when evaluating the economic value of hydropower.
In optimization the Preferred Customer Energy is a variable. The optimization adds a constraint that limits the energy consumed by preferred customers to the energy limits of the reservoirs in the Preferred Customer subbasin by automatically adding the following constraint when the preferred customer method is selected.
The first sum is over the subbasin reservoirs that are optimized while the second sum is over the subbasin reservoirs that are not optimized, but instead are part of allocated energy. In the first case, the maximum energy value is accessible through the configuration menu of the energy slot on each reservoir. In the second case, the Allocated Maximum slot on the thermal object holds a value for each time step.
Typically, when preferred customer energy is used, the modeler will add a prioritized constraint to the optimization requiring that the preferred customer energy be met. The Energy demand must be specified on a slot on a data object.
As in simulation, the Preferred Customer Energy is subtracted from Allocated Energy in the economic evaluation.
Note:  Although still shown in the interface, this method no longer does anything.
Slots Specific to This Method
Preferred Customer Energy
Type: Agg Series Slot
Units: Energy
Description: Load for preferred customers stated as an energy.
Information:  
I/O: Input or Output
Regulation
Regulation is one of the ancillary services that hydropower plants can supply in addition to power to increase the reliability and flexibility of the power system to adjust to fluctuations in power demand and supply. When a plant is regulating it will follow the load within some prescribed band of power rather than generating a fixed amount of power. Typically, regulation is a valuable service that can be provided efficiently by hydropower compared to alternative power sources. In locations where regulation is marketed it usually commands a solid premium above the price of the power generated. This value is partially reduced by the increased maintenance costs associated with regulation.
There are three methods in this category: One Sided Regulation, Two sided Regulation and One and Two Sided Regulation. The design of one sided regulation is almost identical to two sided regulation except that there are separate calculations for regulation up and regulation down. The One and Two Sided Regulation method will allow the user to use both approaches within a single model.
* None
Regulation services are not evaluated.
* Two Sided Regulation
Regulation services are valued as a piecewise linear function of the amount of regulation provided minus the additional operating costs (wear and tear, maintenance, etc.) associated with regulation. The piecewise linear valuation is analogous to the block hydro method of valuing generation (see “Preferred Customer” for details). All of the associated slots for this method have a compatible slot in the block hydro method. The operating costs are simply the sum of individual operating costs calculated on the power reservoirs that are providing regulation.
Two sided regulation assumes that frequency regulation is scheduled with an equal amount of regulation up and regulation down available, and a single valuation for this ancillary service. In contrast, one sided regulation allows regulation up and regulation down to be separate ancillary services with separate amounts scheduled and usually valued differently.
The System Regulation slot holds the total two sided regulation for all power reservoirs linked to it. The value of marginal value of regulation is a non-increasing function of the amount of regulation. In RiverWare, this function is modeled as a series of discrete blocks with decreasing (or equal) marginal values of regulation. These values are in the Regulation Block Costs slot. The amount of each block used in the valuation is in the Block Regulation slot. These blocks are used in order of most valuable to least valuable.
The Regulation Marginal Value and Previous Regulation Marginal Value slots hold the marginal value of increasing and decreasing regulation respectively. If the valuation partially uses a block, then both the Regulation Marginal Value and Previous Regulation Marginal Value slots will have the value of that block. If instead, say N blocks are fully used, and Block N+1 is unused, then Regulation Marginal Value will have the value of Block N+1 and Previous Regulation Marginal Value will have the value of Block N.
This method requires either Calculate Linear Economic Value or Calculate Block Economic Value or method to be selected. See “Calculate Linear Economic Value” and “Calculate Block Economic Value” for details.
Simulation and Optimization use the following equation to calculate the value of regulation by summing over blocks.
The energy in the regulation blocks is constrained to equal the total system regulation (converted from power to energy by multiplying by the timestep).
Slots Specific to This Method
Block Regulation
Type: Agg Series Slot
Units: Energy
Description: Each column is the use of a regulation block in the new optimization system. The slot maximum value is used for the block size. The total equals the System Regulation.
Information: Used in the optimization formulation of regulation.
I/O: Output
Marginal Regulation Costs
Type: Agg Series Slot
Units: $/Power
Description: The value of one additional unit of regulation.
Information:  
I/O: Output
Previous Marginal Regulation Costs
Type: Series Slot
Units: $/Power
Description: The cost of reducing regulation by one unit.
Information:  
I/O: Output
Regulation Block Capabilities
Type: Table Series Slot
Units: Power
Description: The size of the each regulation block.
Information: The length of the piecewise linear segments in the value of regulation function.
I/O: Input
Regulation Block Costs
Type: Agg Series Slot
Units: $/Power
Description: The value of regulation for each regulation block.
Information: The slope of the piecewise linear segments in the value of regulation function.
I/O: Input
Regulation Energy
Type: Agg Series Slot
Units: Energy
Description: This slot has one column for each block of regulation. The values represent the energy in each block that was used to value the regulation generated during the run. At most one block will have a value that is strictly between zero and the size of the block, the Regulation Block Capability. The preceding blocks will be used entirely and the regulation energy will equal the block size. The succeeding blocks will be unused.
Information:  
I/O: Output
Regulation Value
Type: Agg Series Slot
Units: $
Description: The calculated value of regulation based on the Regulation Block Costs.
Information:  
I/O: Output
System Operating Cost
Type: MultiSlot
Units: $
Description: The sum of operating costs from regulation for all linked reservoirs.
Information:  
I/O: Output
System Regulation
Type: MultiSlot
Units: Power
Description: The total regulation summed from the linked power reservoirs.
Information:  
I/O: Output
* One Sided Regulation method
The value of one sided regulation is philosophically similar to two sided regulation. The only difference is that regulation up and regulation down have separate slots and separate valuations. Physically, this may lead either to solutions that use only one side of regulation or solutions that use both sides, but perhaps unevenly. For one sided regulation, there are two slots for every analogous slot in two sided regulation, an Up slot and a Down slot. Similarly, the System Regulation Up and System Regulation Down slots should be linked to Regulation Up and Regulation Down respectively on power reservoirs. For more detail on the specific calculations, see the description of two sided regulation.
Note:  Although the method can be selected and slots will be instantiated, this method has not been implemented yet.
Slots Specific to This Method
The following slots are instantiated when this method is selected.
System Regulation Up
Type: MultiSlot
Units: Power
Description: Total system regulation up
Information: This slot is used to link the Thermal object to each reservoir’s Plant Regulation Up slot.
I/O: Output only
Block Regulation Up
Type: AggSeriesSlot
Units: Energy
Description: The blocks of energy used in the valuation.
Information: The sum of these blocks equals the System Regulation Up. The value of each block is given in Regulation Up Block Costs.
I/O: Output
Regulation Up Block Costs
Type: AggSeriesSlot
Units: PowerCost
Description: The data to value each block of regulation up.
Information:  
I/O: Input
Regulation Up Value
Type: SeriesSlot
Units: Value ($)
Description: The total value of regulating up.
Information: It is calculated as the sum of the value of the blocks used
I/O: output
Regulation Up Marginal Value
Type: SeriesSlot
Units: PowerCost
Description: This is the incremental value of the regulating up block being used.
Information: If regulation is between blocks, this is the value of the next block. This value is only calculated in simulation.
I/O: Output only
Regulation Up Previous Marginal Value
Type: SeriesSlot
Units: PowerCost
Description: This is the incremental value of the regulating up block being used.
Information: If regulation is between blocks, this is the value of the previous block. This value is only calculated in simulation.
I/O: Output only
System Regulation Down
Type: MultiSlot
Units: Power
Description: Total system regulation down
Information: This is used to link the Thermal object to each reservoir’s Plant Regulation Down slot.
I/O: Output only
Block Regulation Down
Type: AggSeriesSlot
Units: Energy
Description: The blocks of energy used in the valuation.
Information: The sum of these blocks equals the System Regulation Down. The value of each block is given in Regulation Down Block Costs.
I/O: Output
Regulation Down Block Costs
Type: AggSeriesSlot
Units: PowerCost
Description: This is the data to value each block of regulation down.
Information:  
I/O:  
Regulation Down Value
Type: SeriesSlot
Units: Value ($)
Description: the total value of regulating down
Information: This is equal to the sum of the value of the blocks used.
I/O: Output
Regulation Down Marginal Value
Type: SeriesSlot
Units: PowerCost
Description: The incremental value of the regulating down block being used.
Information: If regulation is between blocks, this is the value of the next block. This value is only calculated in simulation.
I/O: Output only
Regulation Down Previous Marginal Value
Type: SeriesSlot
Units: PowerCost
Description: The incremental value of the regulating down block being used.
Information: If regulation is between blocks, this is the value of the previous block. This value is only calculated in simulation.
I/O: output only
System Operating Cost
Type: MultiSlot
Units: Value ($)
Description: Total system operating cost
Information: This used to link the Thermal object to each reservoir’s Operating Cost slot.
I/O: Output
Method Details
The design of One Sided Regulation is almost identical to Two Sided Regulation except that there are separate calculations for regulation up and regulation down.
• Regulation Up Value = Sum over blocks (Regulation Up Block Costs * Block Regulation Up)
• Regulation Down Value = Sum over blocks (Regulation Down Block Costs * Block Regulation Down)
* One and Two Sided Regulation method
This method allows the user to perform both one and two sided regulation in a single model. The slots added by this method include all of those for one sided regulation listed above and those for two sided regulation listed in the online help. This method will simply call the two sided regulation method, then call the one sided regulation method.
Note:  Although the method can be selected and slots will be instantiated, this method has not been implemented yet.
Linear Economic Value
* None
No evaluation is made.
* Calculate Linear Economic Value
This method applies a time dependent linear value to power generated. This method is also known as POSE or System Lambda. The order of power source evaluation doesn’t matter, only which power sources are being evaluated, because of the linear valuation. In general, the calculation is a simplified version of the existing block calculation. The value of hydropower is in the Linear Hydro Costs series slot.
The power sources to use in the evaluation are selected in the Linear Power Sources Used table slot. The possible power sources are conventional hydropower, pumped storage, and allocated power. The calculated value of each type of power is output to a corresponding series slot.
Allocated power is constrained by minimal and maximal power generation for each time period combined with periodic total energy requirements. The power is allocated for maximal economic gain in coordination with other power sources.
After calculating the individual economic components for each time period, the totals for all time periods are placed in the Linear Total Values table slot.
Slots Associated with the Calculate Linear Economic Value Method
Linear Hydro Costs
Type: Series Slot
Units: PowerCost
Description: The value of each unit of hydropower generated.
Information: This method does not have Marginal Operating Cost or Previous Marginal Operating Cost slots because the values would be the same as this slot.
I/O: Input
Linear Power Sources Used
Type: Table Slot
Units: None
Description: One row for each power source and one column with a 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
Linear Conventional Replacement Value
Type: Series Slot
Units: None
Description: The calculated value of conventional hydropower using linear evaluation.
Information:  
I/O: Output
Linear Pump Replacement Value
Type: Series Slot
Units: Value
Description: The calculated value of net hydropower generated by pumps using linear evaluation.
Information:  
I/O: Output
Linear Allocated Replacement Value
Type: Series Slot
Units: Value
Description: The calculated value of allocated hydropower using linear evaluation.
Information:  
I/O: Output
Linear Avoided Operating Cost
Type: Series Slot
Units: Value
Description: The combined value of conventional, pump, and allocated hydropower using linear evaluation.
Information:  
I/O: Output
Linear Net Avoided Cost
Type: Series Slot
Units: Value
Description: Linear Avoided Operating Cost minus the value of water used for spill or generation.
Information:  
I/O: Output
Linear Total Values
Type: Table Slot
Units: None
Description: The sum over time for several slots used in the linear economic evaluation.
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
Allocated Minimum
Type: Agg Series Slot
Units: Power
Description: The 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: The 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: The 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: The 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: The sum of allocated energy across projects.
Information: Only used in optimization to assist in mathematical representation.
I/O: Output
Block Economic Value
* None
No evaluation is made.
* Calculate Block Economic Value
This method applies a time dependent piecewise linear, or block, value to power generated. 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 a piecewise linear function of power. The piecewise function can vary by time period. While there is no direct linkage to thermal sources of power, one interpretation of the piecewise linear function is that it represents the coordinated reduction in other power sources as a result of hydropower generation. This method does not attempt to meet an explicit load, rather the load is assumed to be included in the process that generates the piecewise linear functions.
The piecewise linear functions are represented by the Hydro Block Costs. The Hydro Block Costs are the slope of the piecewise linear segments, or alternatively the value of a unit of power. The piecewise linear function is assumed to be concave: the costs are assumed to decrease as the block number increases.
Slots Associated with the Calculate Block Economic Value Method
Hydro Block Costs
Type: Agg Series Slot
Units: PowerCost
Description: The value of each unit of hydropower generated.
Information: The columns represent the power blocks which are assumed to have a non increasing value for power. The number of columns with valid values should equal the Number of Hydro Blocks scalar slot value.
I/O: Input
Hydro Block Use
Type: Agg Series Slot
Units: Energy
Description: The blocks used to value hydropower.
Information: The sum of the blocks should equal the hydropower generated unless too few blocks are specified. The user must input the size of the blocks. The slot configuration dialog should be used to set the Minimum to zero and the Maximum to the desired block size. The Maximum values replace the previous Hydro Block Capacity slot. Maximum values must be entered for at least the same number of columns specified in the Number of Hydro Blocks scalar slot.
I/O: Input
Number of Hydro Blocks
Type: Scalar Slot
Units: None
Description: The maximum number of hydro blocks that could potentially be used.
Information: This value should equal the number of columns in Hydro Block Costs with valid values. If the number in this slot is greater than the number of columns in Hydro Block Costs with valid values, the run will abort with an error message.
I/O: If not input it will default to the total number of columns in Hydro Block Costs.
Block 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
Block Marginal Operating Cost
Type: Series Slot
Units: PowerCost
Description: The additional marginal value of an extra unit of hydropower.
Information:  
I/O: Output
Block Previous Marginal Operating Cost
Type: Series Slot
Units: PowerCost
Description: The additional marginal value of the previous unit of unit of hydropower generated.
Information: This value will be the same as the Block Marginal Operating Cost if hydrogeneration is in the middle of a block.However, the hydro generation for some time periods may exactly match the full use of some number of blocks. 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 blocks.
I/O: Output
Block Tolerance
Type: Scalar Slot
Units: Power
Description: The tolerance for considering a solution to have hydrogeneration exactly equal to some number of blocks.
Information: Floating point arithmetic usually requires a tolerance for comparing numbers. In this case, if the values are equal within the tolerance, then the Block Previous Marginal Operating Cost will have a different value than the Block Marginal Operating Cost. This slot used to be a Table Slot.
I/O: Input
Block Conventional Replacement Value
Type: Series Slot
Units: None
Description: The calculated value of conventional hydropower using block evaluation.
Information:  
I/O: Output
Block Pump Replacement Value
Type: Series Slot
Units: Value
Description: The calculated value of net hydropower generated by pumps using block evaluation.
Information:  
I/O: Output
Block Allocated Replacement Value
Type: Series Slot
Units: Value
Description: The calculated value of allocated hydropower using block evaluation.
Information:  
I/O: Output
Block Avoided Operating Cost
Type: Series Slot
Units: Value
Description: The combined value of conventional, pump, and allocated hydropower using block evaluation.
Information:  
I/O: Output
Block Net Avoided Cost
Type: Series Slot
Units: Value
Description: Block Avoided Operating Cost minus the value of water used for spill or generation.
Information:  
I/O: Output
Block Total Values
Type: Table Slot
Units: None
Description: The sum over time for several slots used in the block economic evaluation.
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
Allocated Minimum
Type: Agg Series Slot
Units: Power
Description: The 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: The 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: The 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: The 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: The sum of allocated energy across projects.
Information: Only used in optimization to assist in mathematical representation.
I/O: Output
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 Associated with the Calculate Thermal Unit Replacement Value 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: The size of the units used to value hydropower.
Information:  
I/O: Input
Thermal Unit Availability
Type: Agg Series Slot
Units: No units
Description: The 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: The 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: The additional marginal value of an extra unit of hydropower.
Information:  
I/O: Output
Thermal Previous Marginal Operating Cost
Type: Series Slot
Units: PowerCost
Description: The 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: The 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: The 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: The calculated value of conventional hydropower using thermal evaluation.
Information:  
I/O: Output
Thermal Pump Replacement Value
Type: Series Slot
Units: Value
Description: The 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: The calculated value of allocated hydropower using thermal evaluation.
Information:  
I/O: Output
Thermal Avoided Operating Cost
Type: Series Slot
Units: Value
Description: The 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: The 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: The 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: The 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: The 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: The 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: The sum of allocated energy across projects.
Information: Only used in optimization to assist in mathematical representation.
I/O: Output
Linear Objective Reported
These methods are used to report the simulation calculation of an objective function value used in optimization. The Linear Objective Reported category is dependent on selecting the Calculate Linear Economic Value evaluation method. The objective value reported consists of a diagnostic message and is also stored in the Linear Total Values table slot. The methods have no dependent slots.
* None
No diagnostic message is printed for the objective.
* Avoided Cost
The Linear Avoided Operating Cost is reported.
* Avoided Cost Plus Cumulative Storage Value
The combined value of the ending Total Cumulative Storage plus the Linear Avoided Operating Cost is reported.
* Avoided Cost Plus Net Cumulative Storage Value
The combined value of the net increase in Total Cumulative Storage during the run plus the Linear Avoided Operating Cost is reported. The net increase equals the Total Cumulative Value of Storage on the last time period of the run minus the Total Cumulative Value of Storage at the starting time step.
* Avoided Cost Plus Net CSV Plus Net Regulation
The combined value of the net increase in Total Cumulative Storage during the run, the Linear Avoided Operating Cost, and the net value of frequency regulation (minus regulation operating costs) is reported.
Block Objective Reported
These methods are used to report the simulation calculation of an objective function value used in optimization. The Block Objective Reported category is dependent on selecting the Calculate Block Economic Value evaluation method. The objective value reported consists of a diagnostic message and is also stored in the Block Total Values table slot. The methods have no dependent slots.
* None
No diagnostic message is printed for the objective.
* Avoided Cost
The Block Avoided Operating Cost is reported.
* Avoided Cost Plus Cumulative Storage Value
The combined value of the ending Total Cumulative Storage plus the Block Avoided Operating Cost is reported.
* Avoided Cost Plus Net Cumulative Storage Value
The combined value of the net increase in Total Cumulative Storage during the run plus the Block Avoided Operating Cost is reported. The net increase equals the Total Cumulative Value of Storage on the last time period of the run minus the Total Cumulative Value of Storage at the starting time step.
* Avoided Cost Plus Net CSV Plus Net Regulation
The combined value of the net increase in Total Cumulative Storage during the run, the Block Avoided Operating Cost, and the net value of frequency regulation (minus regulation operating costs) is reported.
Thermal Objective Reported
These methods are used to report the simulation calculation of an objective function value used in optimization. The Thermal Objective Reported category is dependent on selecting the Calculate Thermal Economic Value evaluation method. The objective value reported consists of a diagnostic message and is also stored in the Thermal Total Values table slot. The methods have no dependent slots.
* None
No diagnostic message is printed for the objective.
* Avoided Cost
The Thermal Avoided Operating Cost is reported.
* Avoided Cost Plus Cumulative Storage Value
The combined value of the ending Total Cumulative Storage plus the Thermal Avoided Operating Cost is reported.
* Avoided Cost Plus Net Cumulative Storage Value
The combined value of the net increase in Total Cumulative Storage during the run plus the Thermal Avoided Operating Cost is reported. The net increase equals the Total Cumulative Value of Storage on the last time period of the run minus the Total Cumulative Value of Storage at the starting time step.
* Avoided Cost Plus Net CSV Plus Net Regulation
The combined value of the net increase in Total Cumulative Storage during the run, the Thermal Avoided Operating Cost, and the net value of frequency regulation (minus regulation operating costs) is reported.
 
Revised: 06/03/2019