SolarSketch: Stylus-first rooftop solar feasibility tool
Stylus-first rooftop solar feasibility MVP. Upload an aerial or map screenshot, calibrate scale, sketch the installable roof and keep-out zones, and get an indicative panel layout plus rough DC/AC capacity and annual energy—all in the browser.
Features
Background image — Upload a satellite or map screenshot; draw directly on it in an SVG canvas (mouse or stylus).
Calibration — Draw a line over a known real-world distance and enter its length in feet to establish pixels-per-foot.
Installable area — Freehand polygon for the roof region where modules may go.
Keep-outs — Multiple polygons for HVAC, paths, and obstructions; layout avoids them. Undo keep-out removes the last one.
Panel layout — Grid of rectangles sized from panel length/width, row spacing, module spacing, and an inner setback buffer. Auto orientation aligns to the longest roof edge and picks the angle that maximizes panel count; manual uses a fixed angle in degrees.
Results — Calibrated scale, roof and keep-out areas (sf), panel count, kWdc, kWac (from DC/AC ratio), annual kWh (from specific yield × kWdc), and layout angle.
https://github.com/pjsk02/Solar-Sketch
