☀️ Solar Power Calculator
Calculate estimated solar panel power generation and financial savings for any location worldwide. Simply click the map, enter your system details, and get instant estimates for daily, monthly, and annual energy output. Our tool uses NREL's PVWatts system data to provide reliable solar production forecasts.
📍 Select Location
💡 Click anywhere on the map to select your location
⚡ System Details
📊 Your Solar Generation Estimate
Daily Average
Monthly Average
Annual Total
Capacity Factor
💰 Estimated Savings
How to Use the Solar Calculator
Our tool provides a reliable estimate of solar energy production in just a few steps. The calculation uses real-world weather data from NREL's PVWatts database.
- Select Location: Click directly on the map, use one of the preset city buttons, or search for a specific address to place the pin on your location.
- Enter System Size: Input the total size of your solar panel system in kilowatts (kW). A typical home system is between 3 kW and 10 kW.
- Adjust Panel Details: The panel tilt will auto-adjust to the optimal angle for your latitude, but you can change it. Select the direction your panels face (azimuth). South is optimal in the Northern Hemisphere.
- Set Electricity Rate: Enter your current electricity rate in $/kWh to estimate your potential savings. You can usually find this on your utility bill.
- Calculate: Click the "Calculate Solar Output" button to see your results. The tool will display daily, monthly, and annual generation, a monthly production chart, and your estimated financial savings.
Common Uses for This Calculator
This calculator is designed for homeowners, businesses, and solar enthusiasts to quickly evaluate the potential of solar energy.
Homeowners
Get a quick, data-driven estimate of how much electricity a rooftop solar system could produce and how much money it could save you. Use it to compare quotes from installers and verify their production estimates.
Businesses
Assess the viability of a commercial-scale solar installation. Model different system sizes to understand the potential return on investment and reduction in your building's carbon footprint.
Education & Research
Students and researchers can use this tool to understand how solar production varies by location, panel orientation, and time of year, using reliable meteorological data as a basis.
Frequently Asked Questions
- How accurate are these estimates?
- Our calculator uses data from NREL's PVWatts® Calculator, which is a widely respected industry standard. It provides a reliable long-term average based on historical weather data but does not predict the exact output for a specific future day.
- What is "Capacity Factor"?
- Capacity factor is the ratio of your system's actual annual output compared to its maximum possible output if it ran at full power 24/7. A typical solar capacity factor is between 10-25%, reflecting that panels only produce power during daylight hours.
- What are "losses"?
- The calculation includes a default loss factor of 14% to account for real-world inefficiencies like dirt on panels (soiling), wiring resistance, inverter inefficiency, and panel degradation over time. This provides a more realistic estimate.
- Why is my panel tilt set automatically?
- For optimal annual production, the ideal panel tilt is usually close to the location's latitude. Our tool automatically sets this for you when you select a location, but you can adjust it to match your specific roof pitch.
- Does this calculator account for shade?
- No, this is a simplified calculator and assumes your panels have a clear, unshaded view of the sun. Shading from trees or nearby buildings can significantly reduce output and is not factored into this estimate.