This study evaluates the use of energy storage technologies coupled to renewable energy sources in rural electrification as a way to address the energy access challenge. Characteristic energy demanding applications will differently affect the operating conditions for off-grid renewable energy systems. This paper discusses and evaluates simulated photovoltaic power output and battery state of charge profiles, using estimated climate data and electricity load profiles for the Altiplanic highland location of Patacamaya in Bolivia to determine the loss of load probability as optimization parameter. Simulations are performed for three rural applications: household, school, and health center. Increase in battery size prevents risk of electricity blackouts while increasing the energy reliability of the system. Moreover, increase of PV module size leads to energy excess conditions for the system reducing its efficiency. The results obtained here are important for the application of off-grid PV-battery systems design in rural electrification projects, as an efficient and reliable source of electricity.