PVCalc vs Sunplot

PV Calc helps homeowners understand whether solar makes financial sense — before calling a single installer. Enter your location and home profile, and the app instantly estimates: • How much solar you need based on your actual electricity usage • Annual energy production from real PVGIS satellite data (EU JRC) • Installation cost after federal and Hawaii state tax credits • Payback time based on your current electricity tariff • Monthly financing options How it works Solar irradiance data is pulled live from the PVGIS v5.2 API (European Commission Joint Research Centre), covering worldwide locations. The app uses your home profile — bedrooms, cooling type, water heater, EVs, and pool — to estimate your consumption and recommend the right system size. Panel types : Choose Budget (300W), Standard (400W), or Premium (500W) panels to see how panel choice affects system size, roof area, and cost. Use PV Calc to compare system sizes, understand your payback timeline, and walk into installer meetings informed.

Every seed packet says "full sun" or "part shade". Almost nobody knows which one their own garden is. Sunplot answers it with a number. Stand where the bed is, hold the phone up, and trace the roofs and trees around you with a finger. Then it walks the whole day a minute at a time and counts only the light that actually reaches that spot. WHY THE ANSWER IS DIFFERENT Other sun apps show you where the sun is. That is the easy half. The half that decides the answer is what stands in the way — the fence, the garage, the lime tree next door. Sunplot measures that skyline with the camera and subtracts it. A bed under open sky and the same bed behind a two-storey terrace are not the same bed, and the number knows it. FREE • Today's hours of direct sun at a spot, and what that means: full sun, part sun, part shade, full shade • What will grow there — 42 plants sorted into will do well, will manage, and too much sun • The map: where the sun arrives from, where it leaves, and where it is right now, with a slider through the day • The sky view: the sun's path drawn over the camera, and the skyline tracing that makes the answer real ONE PAYMENT UNLOCKS • The whole year at a spot — when full sun starts and ends, and the weeks it gets none at all • As many spots as you like — the bed by the fence and the bed by the garage answer differently • Which is better? Every spot side by side, ranked • A word before the sun arrives, so a short winter afternoon is not missed • The home screen widget One payment. No subscription, nothing renews, nothing to cancel. HONEST ABOUT WHAT IT KNOWS The compass in a phone can be badly wrong, and most sun apps draw a confident line anyway. Sunplot says so on screen when it does not trust its own reading. Before you have traced anything it labels the figure as open sky — the most the spot could get — instead of pretending to know. It is a gardening and planning tool, not a survey instrument. Check anything expensive against a professional measurement. NOTHING LEAVES THE PHONE No account, no server, no analytics, no third-party code, and nothing to sign up for. Everything is worked out on the device and stays there. It works with no signal at all. GOOD FOR Vegetable beds, borders and allotments. Balconies and window boxes. Greenhouses and cold frames. Roof pitches for solar panels. Working out which corner will take a shade planting, and which window a houseplant will survive.