Peak Sun Hours (PSH)

Peak sun hours measure a location’s daily solar resource as equivalent hours of full-strength sunshine (1,000 W/m²). Most Indian cities receive 4.5–6 peak sun hours per day averaged across the year.

PSH is not daylight hours — a 12-hour day in Mumbai delivers about 5.2 PSH. Rajasthan and Ladakh sit at the top of India’s range (5.8–6.0), the Northeast at the bottom (~4.2). Multiply system kWp × PSH × performance ratio to estimate daily units.

Part of the HUM Solar Glossary — 75+ plain-language definitions for India’s solar ecosystem, maintained as a neutral reference. Browse all terms →