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Energy out after storage losses
Find how much energy you get back out of a battery after round-trip charge/discharge losses for its chemistry.
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Looking for a definition or a quick answer? See the solar & battery glossary for terms used on this page, or the FAQ for common sizing questions. For the full explanation, read the round-trip efficiency guide.
Sources & standards
- IEEE 1013 — Recommended Practice for Sizing Lead-Acid Batteries for Stand-Alone Photovoltaic Systems — Widely used engineering practice for days-of-autonomy and depth-of-discharge sizing methods, referenced here for the general sizing approach.
- IEC 62619 — Safety Requirements for Secondary Lithium Cells and Batteries for Industrial Applications — International safety-testing standard for LiFePO4 and Li-ion (NMC) cells used in stationary storage.
Estimates for planning only. Verify with a meter and follow NEC / local code; have a licensed installer confirm any system before purchase or wiring. See the methodology for formulas and sources.