How much free energy is falling on your roof right now? NoxSolar puts solar panel planning in your pocket. Everything you need to calculate your solar resource, estimate panel yield, and project financial returns β all in one place, on your phone, standing in your garden. No convoluted websites, no spreadsheets, no browser tabs, no accounts, no sign-ups. Point your phone at the roof. Punch in the numbers. Get answers. SOLAR RESOURCE LOOKUP See exactly how much sunlight your location receives. NoxSolar pulls satellite-derived irradiance data from NASA POWER β 40+ years of records covering every location on Earth. Monthly and annual breakdowns of Global Horizontal Irradiance (GHI), Direct Normal Irradiance (DNI), and Diffuse Horizontal Irradiance (DHI), with plain-English explanations of what they mean. Sunrise, sunset, and day length for today. A clear rating from LOW to EXCEPTIONAL so you know where you stand. PANEL YIELD CALCULATOR Enter your panel wattage and count (or pick from common system presets), set your roof orientation using the built-in compass, choose your roof pitch with a visual diagram, and estimate shading. NoxSolar calculates your annual electricity yield in kWh, broken down by month, with contextual comparisons β "enough for a typical 3-bed house" or "you're basically a small power station." Where available, calculations are cross-referenced with PVGIS (European Commission) for higher accuracy. FINANCIAL PROJECTIONS Input your electricity rate, export tariff, and installation cost. See your payback period, annual savings from self-consumption and export, 25-year cumulative projection with an interactive chart, return on investment, and COβ offset. A full year-by-year breakdown table shows exactly when you cross into profit. Battery toggle automatically adjusts self-consumption estimates. LOCATION COMPARISON Compare your solar resource against benchmark cities worldwide β from Shetland to the Sahara. See where you sit against your national average. Add any location to compare side-by-side with grouped monthly charts. BUILT FOR REAL PEOPLE Large text, large touch targets, large input fields. Designed to be used outdoors in sunlight with cold fingers. No jargon without a friendly explanation right next to it. Every assumption is documented in the About section β what's configurable, what's fixed, and why. KEY FEATURES β’ NASA POWER satellite data for any location on Earth β’ Compass-based roof orientation β point your phone where your roof faces β’ Visual roof pitch selector with animated diagram β’ Monthly irradiance and yield charts β’ 25-year financial projection with year-by-year table β’ Payback period, ROI, and COβ offset calculations β’ Location comparison against global benchmarks β’ Works offline once data is cached β’ Supports GBP, EUR, and USD β’ Light and dark mode β’ No subscriptions, no in-app purchases, no ads β’ No account required, no data collected NoxSolar is a planning and estimation tool. It is not a substitute for a professional site survey. Financial estimates are illustrative β consult a qualified installer for detailed system design. Solar irradiance data from NASA POWER and EU PVGIS. The kind of tool you use before you call the installer, so you walk into that conversation knowing your numbers.