Work out solar elevation angle instantly with clear inputs, formula shown and shareable results.
The solar elevation formula combines latitude, declination and hour angle: sin(altitude) = sin(lat)sin(dec) + cos(lat)cos(dec)cos(H). At 40 degrees latitude with 20 degrees declination and two hours past noon, the Sun stands 56.2 degrees up. Relative air mass, near 1.2 here, sets how much atmosphere the beam crosses and therefore the irradiance available.
Solar elevation
sin(alt) = sin(lat) sin(dec) + cos(lat) cos(dec) cos(H)
Hour angle
H = 15 degrees per hour from solar noon
The Sun directly overhead, one atmosphere thickness. AM1.5 is the standard test condition for solar panels, corresponding to about 48 degrees elevation.
Because both the cosine projection onto the panel and the atmospheric path length depend on it, so output falls steeply at low sun.