Backup reserve

Backup reserve keeps part of the battery capacity available at all times. Regular operation is normally not allowed to discharge that part. The reserve provides backup energy during grid outages and protects battery life by preventing deep discharges. On Solis systems the Reserve SOC applies in all operating modes. The Peak Shaving Baseline SOC is a separate, usually higher floor that only limits discharge for peak shaving. In SolisCloud the Battery Reserve Switch enables the reserve and the Reserved SOC sets its percentage. The reserved energy is only used if the grid fails, and Allow Grid Charging lets the system recharge from the grid to hold the reserve. On the SMA Sunny Boy Smart Energy, you set the battery reserve under the backup settings in Energy management or with the SMA 360° commissioning wizard. For SolarEdge Home Hub systems, the energy available for backup depends on the reserve percentage and the minimum state of energy. When choosing the reserve, think about when an outage might happen, for example a weather event or a utility shutoff. To size the reserve, subtract the expected PV yield from the daily household demand. In an SMA planning example this gave 45% of a 10 kWh battery as the winter outage reserve.

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• sentence 3: support check: partial - Reserve SOC applying to all modes and peak shaving baseline limiting only peak shaving are stated, and the baseline is described as generally more conservative (higher), but the passages don't state this is specific to Solis systems.
• sentence 5: support check: partial - Passage says backup settings including battery reserve are in Energy management or the SMA 360° wizard, but doesn't name the Sunny Boy Smart Energy product.
• sentence 6: support check: partial - Backup reserve energy depends on reserve percentage and minimum state of energy and outage timing considerations are listed, but the passage doesn't name Home Hub specifically (only SolarEdge Home Battery) and the considerations are phrased as questions.
• sentence 7: support check: partial - The example subtracts PV yield from demand giving 4.5 kWh = 45% of 10 kWh for winter grid failure, but the passage doesn't explicitly state it as a general sizing rule or name SMA. -->