pvperfsolar performance modeling

Reference / Solar position

Model option

NREL SPA

NREL's Solar Position Algorithm, accurate to 0.0003°

Inputs used: Latitude, Longitude, Time zone, Altitude, Step, Station pressure, Ambient temperature

Method

The sun position comes from the full Solar Position Algorithm of the National Renewable Energy Laboratory: the position of the Earth from periodic series, the nutation and obliquity of its axis, the aberration of light, the sidereal time, and the parallax from the observer's position on the Earth's surface. The apparent height includes atmospheric refraction from the pressure at the site elevation. The algorithm is accurate to 0.0003° over the years −2000 to 6000.

References

  1. Reda & Andreas 2008, Solar Position Algorithm for Solar Radiation Applications, NREL/TP-560-34302

API

site.sun_model = spa