SunVault systems are available in both 13 kWh and 26 kWh configurations. The kWh rating represents the total energy capacity of the system. The length of time that SunVault will operate in backup will depend on how much energy is stored in the battery at the start of the power outage, how much energy you use during the outage, the duration of the power outage, and the ability to recharge your battery during daylight hours (due to weather).
For example, let’s say your home’s energy loads both totaled and then remained relatively constant at 3 kW. A 13 kWh SunVault system will power the home for about 4 hours (13 kWh ÷ 3 kW = estimated 4 hours) if fully charge at the start of the outage. If the outage occurs during the day when the sun is shining—and solar energy from your rooftop system is available¬—the system will be able to sustain the home for longer by supplying power from solar panels as well. When the solar energy available is greater than the home loads, solar will also recharge the battery in off-grid operation.
Note: The above example scenario is based on a consistent total load and your SunVault being fully charged at the start of the power outage. The scenario does not account for a charge level that’s something less than full; lower energy conversion efficiencies at low state of charge (SOC); or operating reserves necessary to support SunVault wakeup attempts during extended power outages.