Solar Storage Match Calculator

Match solar production to storage capacity for coverage and surplus insights.

kWh
kWh
kWh
%
kWh
%

Quick Facts

Storage
Coverage
Batteries cover night usage
Surplus
Export
Excess can be stored or exported
Efficiency
Matters
Losses reduce usable energy
Decision Metric
Match %
Aim for 80%+ coverage

Your Results

Calculated
Match Percent
-
Usage covered by solar+storage
Storage Coverage
-
Night usage covered
Surplus
-
Daily surplus energy
Deficit
-
Daily deficit energy

Strong Match

Your defaults show a strong match between solar and storage.

What This Calculator Measures

Match solar production to storage capacity to estimate coverage and surplus.

By combining practical inputs into a structured model, this calculator helps you move from vague estimation to clear planning actions you can execute consistently.

This calculator estimates how well your storage size matches daily solar production.

How to Use This Well

  1. Enter daily solar and usage.
  2. Add battery capacity and usable percent.
  3. Set night usage and efficiency.
  4. Review match percent and surplus.
  5. Adjust system sizing as needed.

Formula Breakdown

Match % = covered usage ÷ total usage
Usable storage: capacity × usable % × efficiency.
Surplus: solar − usage.
Deficit: usage − solar.

Worked Example

  • 24 kWh solar and 20 kWh usage yields 4 kWh surplus.
  • Usable battery covers most night usage.
  • Match percent shows total coverage.

Interpretation Guide

RangeMeaningAction
80–100%Strong match.High coverage.
60–79%Good match.Consider a larger battery.
40–59%Moderate match.Increase solar or storage.
<40%Low match.Reassess system sizing.

Optimization Playbook

  • Increase storage: boost night coverage.
  • Improve efficiency: reduce losses.
  • Shift loads: move usage to daylight.
  • Review seasonally: update solar production.

Scenario Planning

  • Baseline: current solar and usage.
  • More storage: add 5 kWh capacity.
  • Higher usage: add 3 kWh daily.
  • Decision rule: aim for 80% match.

Common Mistakes to Avoid

  • Ignoring round-trip efficiency.
  • Using peak solar instead of daily average.
  • Underestimating night usage.
  • Not updating seasonally.

Implementation Checklist

  1. Estimate daily solar output.
  2. Measure night usage.
  3. Apply battery usable percent.
  4. Review match percent.

Measurement Notes

Treat this calculator as a directional planning instrument. Output quality improves when your inputs are anchored to recent real data instead of one-off assumptions.

Run multiple scenarios, document what changed, and keep the decision tied to trends, not a single result snapshot.

FAQ

What is a good match percent?

Many households target 80% or higher.

Does battery size matter?

Yes, more capacity covers more night usage.

Why include efficiency?

Battery losses reduce usable energy.

Related Calculators