Reducing Performance Loss Due to Backtracking Error Through Use of Half Cut Cell Modules

Abstract

Backtracking is typically used in PV systems which employ single axis tracking to reduce the performance losses that would result from row to row shading if optimal tilt angles were used at all times. Although a backtracking algorithm to eliminate shading is straightforward in theory, it becomes more complex in real world installations. This paper will demonstrate the advantages in energy generation that can be achieved by using half cut cell modules as opposed to standard full cell modules when a more complex terrain causes shading on adjacent rows in the morning or evening. It is shown that arrays that use half cut cell modules produce significantly more energy than full cell modules when exposed to a backtracking error that causes minimal shading in a large proportion of the strings connected to a particular inverter.