Solar Inverter Size Calculator

How Solar Inverter Size works

The governing expression is inverter kW = array kW ÷ DC:AC ratio. Solar Inverter Size uses Array DC rating, DC-to-AC ratio to report Suggested inverter rating.

With the loaded values, suggested inverter rating evaluates to 6.00 kW. Vary one measured quantity so the source of the difference stays clear.

Inputs for Solar Inverter Size

Array DC rating and DC-to-AC ratio belong to Solar Inverter Size. Keep source units with array dc rating.

Sample entries show the formula in use. They are not substitute ratings for selected equipment.

Array DC rating

Example entry: 7.2 kW.

DC-to-AC ratio

Example entry: 1.2.

Reading the Solar Inverter Size result

This output represents Solar Inverter Size.

Keep the calculated requirement separate from the rating ultimately selected.

Measurement and units

Use site-specific irradiance, temperature, shading, equipment limits, and measured system losses. Check prefixes on array dc rating.

A fair comparison keeps units, measurement point, and operating condition consistent.

Limits of this calculation

Clipping and local interconnection limits need separate review. Use Off-Grid Battery Bank Calculator as the follow-up for required storage.

The calculation focuses on the named relationship and its entered variables. Unentered effects remain outside Solar Inverter Size.

A useful Solar Inverter Size comparison

Save the initial suggested inverter rating before adjusting array DC rating. A low and high case is more informative than adding an unexplained safety factor after the calculation.

Document the alternate array dc rating source.

Solar Inverter Size record notes

Record source and operating details for array dc rating.

Retain raw suggested inverter rating beside its selected rating.