SunVault enables you to store and use your solar energy when you need it—both when the utility grid is available and when it’s down. For backup operation we recommend maintaining a portion of your stored energy so that you're ready for an unexpected power outage.
This portion is defined as the Reserve Charge level, and you may set it to any value between zero and 50%, in either Self-Supply mode or Cost Savings mode (but not in Reserve mode as it "reserves” stored energy for backup use only).
You can set your Reserve Charge level in the mySunPower app from the SUNVAULT tab. Simply tap EDIT to select your Operating Mode and to set the Reserve Charge level.
SunVault will use energy from your solar system (not from the grid) to charge itself up to the Reserve Charge level that you set. Once that level is achieved, SunVault will then serve your home energy needs depending on the Operating Mode that you select.
Each evening, SunVault uses a small amount of energy to power itself and recharges again when solar energy is available the next day. (During the evening, the SunVault state of charge may dip below the Reserve Charge in order to power itself.)