Tools to map sunlight and assess solar potential
Several tools and apps help homeowners map sunlight on a property, estimate energy production, and visualize panel layouts. These range from free consumer apps to professional-grade software.
Popular consumer tools
- Online rooftop solar calculators: Many solar providers offer web-based tools that use satellite imagery to estimate panel placement and production.
- Mobile apps: Smartphone apps can measure sun angles, create sun-path diagrams, or use augmented reality to visualize panels.
Professional tools and services
- LiDAR and GIS-based platforms: These use high-resolution elevation and building data to model shading and sun exposure accurately.
- PV system design software: Tools used by solar professionals can simulate detailed production using local weather and irradiance data.
What to look for in a tool
- Accuracy of shading analysis and sun-path modeling
- Ability to input roof tilt and azimuth (orientation)
- Local solar resource or irradiance data inclusion
- Exportable reports for permitting or installer quotes
Practical tips
- Use a combination of a free satellite-based estimator for rough screening and a professional shading survey for precise planning.
- For do-it-yourself homeowners, smartphone apps that log sunlight over time provide helpful on-site data.
Choosing the right tool depends on the level of precision needed: simple estimates are fine for initial interest, while rooftop LiDAR or professional surveys are best for final system design.