About this Solar Calculator

Our mission, methodology, and the team behind the tool

Our Mission

Solar Insolation Calculator was created with a simple mission: to make solar energy more accessible by providing accurate, easy-to-understand information about solar potential for any location worldwide.

We believe that the transition to renewable energy is one of the most important challenges of our time, and that solar power will play a crucial role in this transition. However, many people are hesitant to invest in solar energy because they're unsure about the potential benefits for their specific location and circumstances.

Our calculator aims to bridge this knowledge gap by providing reliable estimates of solar insolation, energy production, and financial returns based on location-specific data and user-defined system parameters. By making this information freely available, we hope to empower individuals, businesses, and communities to make informed decisions about solar energy.

Our Data Sources

The accuracy of our calculator depends on the quality of the data it uses. We rely on authoritative sources:

NREL (National Renewable Energy Laboratory): NREL provides comprehensive solar radiation data worldwide. Their dataset includes parameters such as global horizontal irradiance (GHI), direct normal irradiance (DNI), and diffuse radiation. NREL's data is considered the gold standard for solar resource assessment.
NREL PVWatts: We use the NREL PVWatts API to calculate solar production based on your specific system parameters and location, providing highly accurate estimates for your particular setup.
Industry Standards: Our performance ratio calculations, degradation rates, and financial models are based on industry standards and peer-reviewed research.

We regularly update our data sources and models to ensure the most accurate results possible.

Our Methodology

Solar Insolation Calculation

We retrieve location-specific solar radiation data from NASA POWER and NREL databases. This data is adjusted for the specific tilt angle and azimuth of the solar panels, as well as local factors like albedo (ground reflectivity).

Energy Production Estimation

We calculate energy production using the formula: Energy (kWh) = Solar Insolation (kWh/m²) × System Capacity (kW) × Performance Ratio. The performance ratio accounts for various system losses and efficiency factors.

Financial Analysis

Our financial models calculate payback period, ROI, NPV, and IRR based on system cost, energy production, electricity rates, and other financial parameters. We account for panel degradation, maintenance costs, and electricity price inflation.

System Optimization

We automatically suggest optimal tilt angles and azimuths based on your location, but allow you to override these with custom values to model specific installation constraints or preferences.

Our calculator is designed to provide estimates that are as accurate as possible given the available data. However, it's important to note that actual results may vary due to local factors such as shading, microclimate variations, and specific equipment characteristics that aren't captured in our models.

For the most accurate assessment, we recommend using our calculator as a starting point and then consulting with a professional solar installer who can perform an on-site evaluation.

Continuous Improvement

We're committed to continuously improving our calculator to provide the most accurate and useful information possible. Our ongoing efforts include:

Incorporating more detailed local weather data to improve production estimates
Adding more advanced financial modeling options
Expanding our database of equipment specifications
Improving the user interface for better accessibility and ease of use
Adding features to compare different system configurations

We welcome feedback from users to help us identify areas for improvement and new features that would be valuable.

Technical Details

Solar Insolation Calculator is built with modern web technologies to ensure fast, reliable performance and a great user experience:

Frontend: Next.js, React, TypeScript, and Tailwind CSS
Data Visualization: Chart.js for interactive, responsive charts
APIs: NREL Data API, NREL PVWatts API
Geocoding: OpenStreetMap Nominatim API for location search
Hosting: Vercel for fast, global content delivery

Our application is designed to be responsive and accessible, working well on devices of all sizes from smartphones to desktop computers.

Contact Us

We welcome your feedback, questions, and suggestions. Please feel free to reach out to us through our contact page.