Storage

mutable struct Storage <: Modification

Storage(;name, file, build_file="")

Storage is represented over sets of time-weighted sequential representative hours for which the following must hold true, for a given storage device:

• Net charge over the interval must equal zero.
• Total charge of the device cannot exceed its maximum charge, or go below zero.
• Initial charge over an interval can be anywhere between 0 and the maximum charge, and is the same initial charge for each time interval.

Arguments

• name - the name of the Modification.
• file - the filename of the storage table, where each row represents a storage device. See also summarize_table(::Val{:storage})
• build_file - the filename of the buildable storage table, where each row represents a specification for buildable storage. See also summarize_table(::Val{:build_storage})

Variables Introduced

• pcap_stor[stor_idx, yr_idx] - The discharge power capacity, in MW, of the storage device.
• pcharge_stor[stor_idx, yr_idx, hr_idx] - The charge power, in MW, for a given hour.
• pdischarge_stor[stor_idx, yr_idx, hr_idx] - The discharged power, in MW, for a given hour.
• e0_stor[stor_idx, yr_idx, int_idx] - The starting charge energy (in MWh) for each interval.

Constraints Introduced

• cons_stor_charge_bal[stor_idx, yr_idx, int_idx] - the charge balancing equation - net charge in each interval is 0
• cons_stor_charge_max[stor_idx, yr_idx, int_idx, _hr_idx] - constrain the stored energy in each hour of each interval to be less than the maximum (function of pcap_stor and the discharge duration column of the storage table). Note _hr_idx is the index within the interval, not the normal hr_idx
• cons_stor_charge_min[stor_idx, yr_idx, int_idx, _hr_idx] - constrain the stored energy in each hour of each interval to be greater than zero. Note _hr_idx is the index within the interval, not the normal hr_idx
• cons_pcap_stor_noadd[stor_idx, yr_idx; years[yr_idx] >= storage.year_on[stor_idx]] - constrain the capacity to be non-increasing after being built. (only in multi-year simulations)
• cons_pcap_stor_prebuild[stor_idx, yr_idx; years[yr_idx] < storage.year_on[stor_idx]] - fix the capacity to zero before being built. (should only happen in multi-year simulations)
• cons_pcap_stor_exog[stor_idx, yr_idx] - constrain the exogenous, unbuilt capacity to equal pcap0 for the first year >= its build year.

Objective Terms

• capex_obj_stor - the capital expenditures to build the storage device, only non-zero in the build year. (function of pcap_stor and capex, and year_on)
• fom_stor - the fixed operation and maintenance costs for the storage device (function of pcap_stor and fom from the storage table)
• vom_stor - the variable operation and maintenance costs for the storage device (function of pdischarge_stor, the vom column of the storage table, and the hour weights get_hour_weights)

Power Balancing Equation

Each storage device can either be on the "gen" side or the "load" side, as specified by the side column.

• "gen" side:
  • pcharge_stor gets subtracted from pgen_bus
  • pdischarge_stor gets added to pgen_bus
• "load" side:
  • pcharge_stor gets added to plserv_bus
  • pdischarge_stor gets subtracted from plserv_bus

modify_raw_data!(mod::Modification, config, data, model)

Change the raw data with mod.

modify_setup_data!(mod::Modification, config, data, model)

Change the setup data with mod.

modify_model!(mod::Modification, config, data, model)

Apply mod to the model, called in setup_model

modify_results!(mod::Storage, config, data)

Modify battery results. Add columns to the storage table for:

• pcap - discharge capacity of the storage device, in MW.
• pcharge - the charging rate, in MW
• pdischarge - the discharging rate, in MW
• echarge - the energy charged in each representative hour (including losses)
• edischarge - Energy that was discharged by the storage device
• ploss - Power that was lost by the battery, counted as served load equal to pcharge * (1-η)
• eloss - Energy that was lost by the battery, counted as served load
• pcap_inv_sim - power discharge capacity invested in the sim
• ecap_inv_sim - 8760 * pcapinvsim

Also saves the updated storage table via save_updated_storage_table.

save_updated_storage_table(config, data)

Saves the updated storage table with any additional storage units, updated capacities, etc.

summarize_table(::Val{:storage})

summarize_table(::Val{:build_storage})