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Solar Panel Calculator
Legal Agreement

Terms of Service

Last Updated: February 2026

1. Educational & Estimating Purpose

All calculations, models, and estimations generated by SolarPanelCalculator.org are intended solely for educational, preliminary planning, and budgeting purposes. Solar irradiance, equipment efficiency, roof geometry, shading, and financial payback vary by specific installation and geographic coordinates.

2. No Professional Engineering Guarantee

While our mathematical models adhere to standard industry formulations (such as NREL PVWatts), nothing on this website constitutes a formal structural, electrical, or engineering design. Users must have their final solar photovoltaic system designed and signed off by a licensed electrician and structural engineer.

3. Limitation of Liability

In no event shall SolarPanelCalculator.org, its authors, or operators be held liable for any damages, financial losses, or installation discrepancies resulting from reliance on the calculators or content provided.