Appendix A: Available Site-Level Signals

The signals described below are available in the Powerhub UI and can be retrieved via the API.

Table 1. Battery Signals
UI Name API Name Description Unit
Battery Apparent Power battery_apparent_power Apparent power calculated from measured real and reactive power at the battery meter. VA
Battery Backup Reserve backup_reserve Amount of energy reserved for power outages. Wh
Battery Breaker Status breaker_open_status Status of battery breaker. Text
Values:
  • Open
  • Closed
Battery Charge Power battery_charge_power Instantaneous real/active power measured at the battery meter used for charging the battery. W
Battery Discharge Power battery_discharge_power Instantaneous real/active power measured at the battery meter used for discharging the battery. W
Battery Energy Charged battery_energy_imported Energy used to charge the battery. Measured at the battery inverter (AC) meter. Wh
Battery Energy Discharged battery_energy_exported Energy discharged from the battery. Measured at the battery inverter (AC) meter. Wh
Battery Energy Remaining battery_expected_energy_remaining Energy remaining in the battery if operated at a nominal temperature of 25⁰C. Wh
Battery Full Pack Energy battery_nominal_full_pack_energy Available energy of the batteries when fully charged and at nominal temperature of 25°C (affected by temperature, degradation, etc.). Wh
Battery to Load Energy battery_to_load_energy Battery energy used to power loads. Wh
Battery Max Charge Power max_charge_power Continuous power available to charge the battery. Available charge power will taper off as the battery reaches a fully charged state. Otherwise, this should be equivalent to the nameplate power rating of the system. W
Battery Max Discharge Power max_discharge_power Continuous power available to discharge the battery. Available discharge power will taper off as the battery reaches a fully depleted state. Otherwise, this should be equivalent to the nameplate power rating of the system. W

Battery Mode
See Powerwall Modes for more information

 command_real_mode Mode configured for battery operation. Text
Values:
  • Off
  • Time Based Control
  • Backup Mode
  • Self-Powered
Battery Reactive Power battery_instant_reactive_power Instantaneous reactive power measured at the battery meter. VAr
Battery Real Power battery_instant_power Instantaneous real/active power measured at the battery meter. W
Battery State of Energy battery_state_of_energy Available energy of the system calculated as a percentage by dividing the nominal energy remaining by the full pack energy. %

battery_expected_energy_remaining_
percentage
Battery Target Reactive Power battery_target_reactive_power Latest reactive power command sent to the battery by the Tesla Site Controller VAr
Battery Target Real Power battery_target_power Latest real power command sent to the battery by the Tesla Site Controller. W
Battery Voltage voltage OR battery_voltage Output AC Voltage of the inverters. V
Hybrid Inverter Real Power RGM inverter_instant_power_rgm Instantaneous real/active power measured at the inverter's Revenue Grade Meter (RGM). W
Hybrid Inverter Energy Produced RGM inverter_energy_exported_rgm Energy generated by the solar system and/or discharged by the battery. Measured at the inverter's Revenue Grade Meter (RGM). Wh
Hybrid Inverter Energy Consumed RGM inverter_energy_imported_rgm Energy consumed by the battery. Measured at the inverter's Revenue Grade Meter (RGM). Wh
Off Grid Fault State off_grid_fault_state Reason why battery is offline during an off-grid (backup) situation. Text
Values:
  • None
  • Wait for Solar - Battery is below 10% and will restart every hour during daylight hours to check for solar to charge from. Toggle Powerwall switch to restart on demand.
  • Wait for User - Battery is empty. Ensure that there is a power source available to charge the battery and toggle the Powerwall switch to restart.
  • Wait for Jumpstart - Battery requires a 12V input to restart.
  • Overload - Battery is overloaded. Reduce load and toggle Powerwall switch to restart.
Table 2. Islanding Controller Signals
UI Name API Name Description Unit
Islander Disconnected islander_disconnected Indicates whether the system is connected to the grid or not. Text
Values:
  • Connected
  • Disconnected
Island Mode island_mode Indicates the state of the islanding controller. Text
Values:
  • Unknown
  • Backup - Capable of providing backup power.
  • Intentional Island - Triggered when manually going into off-grid mode by using "Go off-grid" feature in the mobile app.
Table 3. Solar Signals
UI Name API Name Description Unit
Solar Apparent Power solar_apparent_power Apparent power calculated from measured real and reactive power. VA
Solar to Battery Energy solar_to_battery_energy Solar energy used to charge the battery. Wh
Solar Energy Imported solar_energy_imported Energy consumption measured at the AC solar production meter. Wh
Solar Energy Produced solar_energy_exported Energy generated by the solar system. Measured at the AC solar production meter. Wh
Solar Energy Produced RGM solar_energy_exported_rgm Solar energy produced as measured by the AC Revenue Grade Meter (RGM). Wh
Solar to Load Energy solar_to_load_energy Solar energy used to power the loads. Wh
Solar Reactive Power solar_reactive_power Instantaneous reactive power measured at the solar production meter. VAr
Solar Real Power solar_instant_power Instantaneous real/active power (AC) measured at the solar production meter. W
Solar Real Power Limit solar_real_power_limit Maximum real power output (AC) allowed. Anything exceeding the real power limit is curtailed. W
Solar Real Power RGM solar_instant_power_rgm Instantaneous solar power produced as measured by the AC Revenue Grade Meter (RGM). This signal is not used for controls. W
Table 4. Grid Signals
UI Name API Name Description Unit
Grid Compliant grid_ready_sync Indicates whether the grid voltage and frequency is within the range specified by the local grid code. Text
Values:
  • Grid Not OK
  • Grid OK
Grid Voltage grid_voltage Voltage measured at the interconnection point. V
Grid Connected Status grid_connected_status Indicates whether the system is connected to the grid or not. Text
Values:
  • "Grid Disconnected" = Off-grid
  • "Grid Connected" = On-grid
Grid Connected Status grid_connected_status Indicates whether the system is connected to the grid or not. Text
Values:
  • "Grid Disconnected" = Off-grid
  • "Grid Connected" = On-grid
Adjusted Grid Energy Buy Price energy_buy_price Price for energy consumed from the grid. $/kW
Real Grid Energy Buy Price customer_energy_buy_price Price for energy consumed from the grid. Configured by the customer or a partner that has access. $/kW
Grid Energy Exported site_energy_exported Energy exported to the grid by on-site generation or storage. Wh
Grid Energy Imported site_energy_imported Energy consumed from the grid by on-site loads or storage. Wh
Adjusted Grid Energy Sell Price energy_sell_price Price for energy exported to the grid. $/kW
Real Grid Energy Sell Price customer_energy_sell_price Price for energy exported to the grid. Configured by the customer or a partner that has access. $/kW
Grid Frequency grid_frequency Frequency of the system, measured at the point of interconnection. Hz
Grid Frequency frequency Frequency of the system. Measured at the point of interconnection. Hz
Grid Neutral to Earth Voltage chassis_voltage Voltage measured between neutral and earth. Available on Gateways outside of North America.  V
Grid Real Power site_instant_power Instantaneous power (AC) measured at the point of interconnection. The meter installed here measures net site demand. W
Grid Services Energy Exported grid_services_energy_exported Energy exported to the grid for a specific grid support program. Wh
Grid Services Energy Imported grid_services_energy_imported Energy consumed from the grid for a specific grid support program. Wh
Grid Services Real Power grid_services_instant_power Instantaneous power (AC) measured at the point of interconnection, used for a specific grid support program. W
Load Energy load_energy_imported Calculated value indicating the energy consumed by the loads. Wh
Table 5. Load Signals
UI Name API Name Description Unit
Loads Dropped loads_dropped Indicates whether loads lost power during a grid transition. Count
Load Real Power load_instant_real_power Calculated value indicating instantaneous power consumption based on measurements at solar, battery, and the point of interconnection. W
Table 6. Generator Signals
UI Name API Name Description Unit
Generator Active Count generator_active_count Number of generators running on site. Count
Generator Apparent Power generator_apparent_power Apparent power calculated from measured real and reactive power. VA
Generator to Battery Energy generator_to_battery_energy Generator energy used to charge the battery. Wh
Generator Energy Exported generator_energy_exported Energy generation measured at the generator Wh
Generator Energy Imported generator_energy_imported Energy consumption measured at the generator Wh
Generator to Load Energy generator_to_load_energy Generator energy used to power the loads. Wh
Generator Reactive Power generator_reactive_power Instantaneous reactive power measured at the generator. VAr
Generator Real Power generator_instant_power Instantaneous real/active power (AC) measured at the generator W