Self-sufficiency rate

The self-sufficiency rate shows how much of a site's electricity use is covered by its own internal power supply. It is the internal power supply divided by the total consumption of the loads over the chosen period. Loads can draw energy from the PV system, from any available batteries, or from the utility grid, and only the grid share counts against self-sufficiency. SMA monitoring reports the figure for a day, a month, a year and the full system lifetime, comparing internal supply with consumption for each period. It is shown alongside the self-consumption rate, which compares self-consumption with PV yield instead of with consumption. On systems with a battery, a direct consumption rate is also shown, which compares direct consumption with yield.

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• sentence 3: support check: partial - The three sources are stated, but the claim that only the grid share counts against self-sufficiency is not stated. -->