SolXY

SolXY is a 3D simulator for planning rooftop solar panel installations. Build your roof in the app, place panels on any slope, and see exactly when and where the sun reaches them — hour by hour, all year round. Designed for the moment before you commit to a solar installer's quote: when nearby buildings cast shadows that limit which roof slopes will actually produce power. SolXY shows you the answer in 3D, on your device, in a few minutes. WHAT YOU CAN DO • Build your home in 3D. Set width, depth, height, and pick from 7 roof types: flat, gable, hip, gambrel, skillion, saltbox, butterfly. • Add the garage, the neighbour's house, and any other building that might cast a shadow. Shadow-casters don't need panels — they just affect the sun calculation. • Place a solar panel array on any roof slope. Configure panel size, rows × columns, gaps, position offsets, and a mounting lift for scaffolding setups. • Set tilt, roll, and yaw to match how the panels are mounted, or enable sun-tracking to see what a tracking installation would do. • Scrub date and hour sliders to watch shadows move across the roof through the day and through the year. • Compute an annual energy yield estimate based on your panel rating, system derate, tilt, and the simulated shading. • Save and load scene configurations as JSON for sharing or backing up your design. SOLAR PHYSICS YOU CAN INSPECT • Real sun position computed from latitude, longitude, and time. • Annual solar paths shown as arcs around your scene. • Per-panel sun rays toggle showing which panels are catching direct sunlight at each moment. • Yearly shading heatmap raycasting hundreds of timestamps against ~0.4 m cells of each roof slope to colour-code total annual sun received — green where it's clear, red where it's blocked. PRIVATE BY DEFAULT • No account. No sign-in. No analytics. No advertising. • Everything runs on your device. Your location, building dimensions, and panel layouts are stored only in local storage and never leave your phone. • Network access (Android's INTERNET permission) is used only to load the bundled offline assets — nothing about your design or location is transmitted. INTERACTIVE TUTORIAL A first-run coachmark tour walks you through every group of controls so you know exactly what each setting does. Replayable from Settings any time. LIMITS YOU SHOULD KNOW • The default yield estimate uses an analytical clear-sky model, which tends to over-estimate annual production by 10–25 % compared to real climate data. Treat the kWh figure as an upper bound, not a quote. • SolXY is a planning aid, not an engineering calculator. Always confirm structural, electrical, and regulatory aspects of your installation with a qualified solar installer in your area.