Azimuth : The angle between true north and the projection of a surface normal to the horizontal plane, measured clockwise from the north. As applied to a Photovoltaic array, 180 degrees azimuth means the array faces south
Young & Company Electric Power Products and Related Engineering Services, Glossary of Electrical Terms, http://www.youngco.com/young2.asp?ID=4&Type=3, CA., USA 2001. (Electr Sfty - Amer) {514}