Solar planning · United Kingdom
Solar sizing for London
Use 3 peak sun hours per day as a rounded first-pass value for London. A 5 kW array with 20% losses would produce about 12 kWh on an average planning day.
Calculate your array
Enter 3 in the solar system size calculator, then add your daily use, roof area, orientation, and shading. Rounded peak-sun-hour planning values from Global Solar Atlas; verify a roof design with site-specific irradiance and shading. Global Solar Atlas.
How to use London sun hours
A 5 kW array at 3 peak sun hours and 20% losses produces about 12 kWh on an average planning day. Multiply your daily demand by 1.25, then divide by 3 to get a first-pass DC size. Monsoon, shading, roof direction, and temperature can move the real result substantially.
Questions to check before buying
- Is the roof free of shade during the strongest solar hours?
- Does the installer use a monthly or seasonal production model?
- Are export limits, battery losses, and local approval rules included?