Solar reference · updated 2026-08-26
Solar sizing by city
Rounded peak sun hours for 8 cities. Use them as a first-pass input, then verify the roof with site-specific shading and irradiance.
| City | Peak sun hours | Confidence |
|---|---|---|
| Dhaka, Bangladesh | 4.5 h/day | approximate |
| Mumbai, India | 5 h/day | approximate |
| Delhi, India | 5.2 h/day | approximate |
| Bengaluru, India | 5.1 h/day | approximate |
| Karachi, Pakistan | 5.5 h/day | approximate |
| Lagos, Nigeria | 4.8 h/day | approximate |
| Phoenix, United States | 5.7 h/day | approximate |
| London, United Kingdom | 3 h/day | approximate |
Use the resource in a sizing estimate
Enter the city value in the solar system size calculator, add losses, and compare the resulting array with your roof area. Rounded peak-sun-hour planning values from Global Solar Atlas; verify a roof design with site-specific irradiance and shading. Source: Global Solar Atlas.