Off Grid Solar Battery Calculator
Estimate off-grid battery autonomy from capacity and daily load. Inputs stay in your browser.
Divide usable battery energy by daily consumption to estimate ideal autonomy.
Context matters.
- Inverter losses, temperature, battery age, surge loads and reserve settings reduce real-world autonomy.
Sources & scope
The calculation guide and this source trail show what the result means, where the rule came from and when it was last reviewed. This is source-and-calculation QA, not a claim of medical, legal, tax or other professional review; time-sensitive decisions still belong with the linked authority.
A visible path from input to answer.
Estimate off-grid battery autonomy from capacity and daily load. The page keeps the calculation scope and its limits beside the result so the output can be checked, copied or revisited.
- Read the record. The calculator uses Battery capacity (kWh), Daily energy use (kWh) and Usable battery capacity (%) supplied in the form.
- Apply the scope. It applies the User-provided values — verify local or contractual assumptions reference and the explicit date, unit and counting conventions shown in the result.
- Expose the checkpoints. Intermediate rows, warnings and timeline events stay visible; the emphasized row identifies the primary checkpoint when one exists.
Divide usable battery energy by daily consumption to estimate ideal autonomy.
- Ideal autonomy2 days
Calculation purpose: Estimate off-grid battery autonomy from capacity and daily load. This is a general planning reference; local conditions, product instructions or personal records can override the estimate.
Numeric inputs are constrained by the field limits and the result keeps the entered units visible. Zero, minimum, maximum and non-finite values are treated as input boundaries.
Rule set 1.1.0 · Last reviewed 2026-08-20 · Next review due 2027-02-20. The source panel below contains the linked evidence.
What to know before using the result.
How is battery autonomy calculated?
Usable battery energy is divided by average daily energy use.
Does the result include inverter losses?
Only if you reduce the usable-capacity input to account for them. The headline is an idealized estimate.
What other factors reduce real autonomy?
Temperature, battery age, surge loads, reserve settings and changes in daily consumption can all shorten it.