Defined term

Peak sun hours

Peak sun hours express daily solar irradiation as the equivalent number of hours at a reference irradiance of one kilowatt per square meter.

Also known as equivalent full-sun hours

measurement · Concept code GS-CONCEPT-033 · Last verified August 20, 2026

Definition and boundaries

Definition

Peak sun hours express daily solar irradiation as the equivalent number of hours at a reference irradiance of one kilowatt per square meter.

Definition claim verification: Verified August 20, 2026

In plain language

When comparing Peak sun hours, keep the unit, time period, measurement boundary, and underlying assumptions the same on both sides.

What it is not

It is not the number of clock hours when the sun is visible and it does not alone predict system output.

Decision context

Why it matters

Use a defined dataset, surface orientation, and period; the value is a convenient energy-equivalent summary rather than a count of bright daylight hours.

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

Primary sources

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