The evaluation of the lifetime of fluorescent lamps and electronic ballast is a current issue in illuminating engineering. The difficulty of carrying out this extensive evaluation by means of time-consuming tests of durability led to the search for a single-factor or shortened durability test that would give a reliable evaluation. This paper presents the results of submitting three samples of 14 different models of DC ballast with fluorescent lamps for photovoltaic (PV) applications, to a durability test of 2 h 45 min on/15 min off, for 10,500 h. An additional sample of each model was used for the measurement of various parameters such as the current crest factor (CCF) and a description is given of the main factors affecting lifetime. As a result of these tests, the CCF is assessed as a lifetime evaluator, together with a regression model that relates this CCF to the relative frequency at which premature breakdown occurs. A possible relationship is suggested between lamp voltage and lifetime, together with some considerations of the effect on lifetime of the state of charge of the battery. (C) 2003 Elsevier Ltd. All rights reserved.