Netzero – Backup Mode

Overview

Netzero supports Backup Mode, a Powerwall operational mode that charges the battery from the grid at a faster rate compared to Self-Powered mode — around 3.3 kW per battery (see Charging Rates below). Backup Mode can also be used to preserve the Powerwall’s charge.

Important notes:

Using Backup Mode

1. Faster Charging from the Grid

Previously, controlled charging of the Powerwall (i.e. not charging in Time-Based Control mode, which cannot be directly controlled) required setting the backup reserve to 100% and resetting it later via automations, charging at about 1.8 kW per battery.

To charge faster — about 3.3 kW per battery — use Backup Mode. Grid Charging must be enabled. Example automation:

Every day at 12:00 AM: Set operational mode to Backup; Set grid charging to Enabled.
Every day at 6:00 AM: Set operational mode to Self-Powered.

Note: To stop charging, switch the mode back to your normal setting (Self-Powered or Time-Based Control). You may also disable Grid Charging if desired.

2. Preserving Powerwall Charge

Backup Mode can also prevent the battery from discharging. This is similar to the Preserve Battery Charge automation (which sets the backup reserve to the current state of charge), but Tesla’s recent changes prevent that method from working between 81–99% state of charge. Backup Mode has no such limitation. To preserve charge, enable Backup Mode with Grid Charging disabled. Example automation:

When vehicle charging starts: Set operational mode to Backup; Set grid charging to Disabled.
When vehicle charging stops: Set operational mode to Self-Powered.

Note: Remember to reset the operational mode to your normal setting, and re-enable Grid Charging if needed.

Charging Rates by Mode

Mode Grid Charging? Typical Rate per Battery Notes
Time-Based Control Required ~5 kW Fastest charging; Tesla controls when charging occurs during off-peak hours.
Backup Mode (Netzero) Required ~3.3 kW Charges from solar (if available) and grid to 100%.
Self-Powered Optional ~1.8 kW Setting backup reserve to 100% (or any value above the current state of charge) forces charging from solar and grid.

Multiple Batteries: Charging rates scale with the number of Powerwalls (e.g., ~6.6 kW for two in Backup Mode), but:

Other grid-charging methods exist (e.g., manual Storm Watch or VPP events), but they cannot be automated in Netzero.