storage.csv

This file is where storage elements are defined. Add one row for each storage component in the model.

Note that Prescient supports more storage properties than what is supported by the standard RTS-GMLC input format. Prescient extends the standard RTS-GMLC file format by supporting a set of additional columns that are not part of the RTS-GMLC standard. Some of these non-standard columns are required by Prescient; Prescient is unable to use standard RTS-GMLC storage.csv files without a few extra columns.

Optional properties can be left out of the CSV file, either by leaving the entire column out of the file, or by leaving values blank. Any missing values will use default values.

Note

Be aware that some default values may prevent a storage element from being utilized as intended. For example, the default End State of Charge defaults to the initial state of charge. If the storage element starts fully charged, the default End State of Charge is set to 1.0, requiring the storage element to be fully charged at the end of each RUC and SCED.

Note

Note for reviewers: As implemented, default values are handled by Egret. If a value is omitted from the CSV file, it is also omitted from the Egret model. Egret then handles the missing value using its own default value logic. The defaults listed in the table below were taken from the Egret source code.

storage.csv Columns

Column Name	Description	Egret	Default Value
GEN UID	The name of a generator on the same bus as this storage element	Used to identify the bus this storage element is attached to. The storage will be placed on the same bus as the named generator. No relationship between the generator and the storage is reflected in the Egret model, other than being placed on the same bus.	Required
Storage	A unique name for the storage element	Used as the storage element name in Egret. Data for this storage component is placed in a dictionary located at ['elements']['generator'][<Storage>].	Required
Max Volume GWh	The maximum storage capacity, in GWh	Converted to MWh, then placed in the storage dictionary as energy_capacity	Required
Initial Volume GWh	The quantity of energy stored in the storage element at the beginning of the simulation, in GWh.	Converted to a fraction of Max Volume GWh, then placed in the storage dictionary as initial_state_of_charge	0.0
Start Energy	The rate at which energy is being drawn from the storage element (if positive), or the rate at which energy is being injected into the storage element (if negative), at the start of the simulation. Units are GW.	First converted to MW. If positive, placed in the storage dictionary as initial_discharge_rate. If negative, placed in the storage dictionary as initial_charge_rate. This column serves the same purpose as either the Initial Charge Rate MW or the Initial Discharge Rate MW column, depending on sign. If a row has a value in the Start Energy column and in the corresponding initial charge/discharge column, the initial charge/discharge column takes precedence and the value in Start Energy is ignored.	0.0
Initial Charge Rate MW	The rate at which energy is being injected into the storage element at the start of the simulation. Units are MW.	Placed in the storage dictionary as initial_charge_rate. Takes precedence over negative values in the Start Energy column.	0.0
Initial Discharge Rate MW	The rate at which energy is being drawn from the storage element at the start of the simulation. Units are MW.	Placed in the storage dictionary as initial_discharge_rate. Takes precedence over positive values in the Start Energy column.	0.0
Inflow Limit GWh	The maximum rate at which energy can be injected into the storage element, in GW Note (The column name says GWh. Should this really be GW instead???). Also, the Egret default is 0.0. Is that a good default? I guess it means “not rechargeable”?	Converted to MW, then placed in the storage dictionary as max_charge_rate	0.0
Rating MVA	The maximum rate at which energy can be drawn from the storage element	Placed in the storage dictionary as max_discharge_rate	0.0
Min Discharge Rate MW	The minimum rate at which energy can be drawn from the storage element	Placed in the storage dictionary as min_discharge_rate	0.0
Min Charge Rate MW	The minimum rate at which energy can be injected into the storage element	Placed in the storage dictionary as min_charge_rate	0.0
Max Hourly Discharge Ramp Up MW	The maximum increase in the discharge rate within a 60 minute period	Placed in the storage dictionary as ramp_up_output_60min	Required Note Required by Egret, has no default. Consider updating Egret to make this optional, with some sort of “Unlimited” default.
Max Hourly Discharge Ramp Down MW	The maximum decrease in the discharge rate within a 60 minute period	Placed in the storage dictionary as ramp_down_output_60min	Required Note Required by Egret, has no default. Consider updating Egret to make this optional, with some sort of “Unlimited” default.
Max Hourly Charge Ramp Up MW	The maximum increase in the charging rate within a 60 minute period	Placed in the storage dictionary as ramp_up_input_60min	Required Note Required by Egret, has no default. Consider updating Egret to make this optional, with some sort of “Unlimited” default.
Max Hourly Charge Ramp Down MW	The maximum decrease in the charging rate within a 60 minute period	Placed in the storage dictionary as ramp_down_input_60min	Required Note Required by Egret, has no default. Consider updating Egret to make this optional, with some sort of “Unlimited” default.
Min SoC	The minimum state of charge the storage element is allowed to be drawn down to. Below this point, the system is not allowed to draw additional energy from the storage element. Expressed as a number between 0 and 1 that indicates the fraction of the maximum storage capacity below which additional energy may not be drawn. A value of 0 means all energy is allowed to be drawn from the storage element; a value of 0.5 means the system must stop drawing energy from the storage element once its stored energy drops below half of its capacity.	Placed in the storage dictionary as minimum_state_of_charge	0.0
Charge Efficiency	The fraction of injected energy that is stored in the storage element. Between 0 and 1.	Placed in the storage dictionary as charge_efficiency	1.0
Discharge Efficiency	The fraction of drawn energy that is injected onto the bus. Between 0 and 1.	Placed in the storage dictionary as discharge_efficiency	1.0
Hourly Retention Rate	The fraction of stored energy that is still stored in the storage element after 60 minutes of idle time. Between 0 and 1.	Placed in the storage dictionary as retention_rate_60min	1.0
Charge Cost	The cost per MW of inflow, before losses due to charge efficiency.	Placed in the storage dictionary as charge_cost	0.0
Discharge Cost	The cost per MW of outflow, before losses due to discharge efficiency.	Placed in the storage dictionary as discharge_cost	0.0
End State of Charge	The minimum state of charge at the end of each RUC and SCED. Between 0 and 1.	Placed in the storage dictionary as end_state_of_charge.	Defaults to the initial state of charge fraction implied by Initial Volume GWh, if specified. If that value is also omitted, defaults to 0.5.