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GridPermit Calculation Methodology

GridPermit uses regional US electricity pricing baselines, solar-yield assumptions, and time-of-use (TOU) energy offset models to generate preliminary educational estimates.

1. System Sizing & Yield Modeling

Estimated solar system size (kW) is modeled from user-entered monthly electric spend divided by regional utility electricity price baselines. Calculations assume standardized regional solar production factors ranging from 1,300 to 1,600 kWh per installed kW annually.

2. Battery Storage Modeling

Battery capacity options (13.5 kWh to 20.0 kWh) are suggested based on evening load offset potentials under common regional time-of-use tariffs. Storage systems capture daytime solar generation for peak evening use.

3. Financial Assumptions & Limitations

Estimates incorporate standard federal tax incentive assumptions where applicable. Payback timelines assume a baseline annual electricity rate increase model. Actual savings vary significantly based on roof tilt, orientation, shading, equipment selection, financing terms, and local utility regulations. These estimates are informational only and require property-specific validation by a qualified installer.