Lifetime Testing of Solar Home Systems
A method to evaluate lifetime aspects of solar home systems (SHSs) is presented together with first test results. The principal factors that cause premature failure of lead-acid batteries have been studied for 6 different SHS configurations and 2 solar lanterns under simulated field conditions. After a 6-month testing period serious battery degradation was observed. Further, applying a constant voltage charge regulator instead of a classical 2-point regulator showed an increased utilization of the energy from the module.