Solar path wise

Sun paths, shadow lengths and direct sun hours, calculated on device. ALGORITHMS Solar position: NOAA Solar Calculator formulation. Julian centuries, geometric mean longitude, mean anomaly, equation of the centre, apparent longitude, obliquity with nutation correction, declination and the equation of time. Refraction: NOAA piecewise model, applied by apparent elevation band. Sunrise and sunset: hour angle from a 90.833° zenith, with polar day and polar night handled as outcomes rather than errors. RADIATION MODEL Air mass: Kasten-Young. Direct normal irradiance: Meinel power law. Diffuse: ten percent of direct, a simplification flagged wherever it is used. Plane of array: beam plus isotropic diffuse plus ground reflected. All of it is a clear sky upper bound. No clouds, no temperature derating, no soiling, no inverter curve. KNOWN LIMITS Sun position is accurate to about 0.02° and…