Defined term

Battery round-trip efficiency

Battery round-trip efficiency is delivered discharge energy divided by charge energy over a defined charge-and-discharge test boundary.

Also known as storage round-trip efficiency

measurement · Concept code GS-CONCEPT-048 · Last verified August 20, 2026

Definition and boundaries

Definition

Battery round-trip efficiency is delivered discharge energy divided by charge energy over a defined charge-and-discharge test boundary.

Definition claim verification: Verified August 20, 2026

In plain language

When comparing Battery round-trip efficiency, keep the unit, time period, measurement boundary, and underlying assumptions the same on both sides.

What it is not

It is not one-way inverter efficiency and it does not state battery capacity or power.

Decision context

Why it matters

Meter location, auxiliary loads, inverter inclusion, state-of-charge endpoints, rate, temperature, and test duration determine the value's meaning.

Decision-context claim verification: Verified August 20, 2026

Information boundary

This page provides general educational context, not a site design, production guarantee, utility determination, contract interpretation, legal opinion, tax conclusion, or individualized financial advice. Verify property, equipment, utility, jurisdiction, program, and agreement details before acting.

Concept relationships

Affects

  • Solar battery storagePublished conceptBattery round-trip efficiency can affect how Solar battery storage is evaluated
  • Payback periodPublished conceptBattery round-trip efficiency can affect how Payback period is evaluated

Primary sources

What to do next

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