Solar and wind power are the two major natural sources of intermittent power in the world. The combination of these sources has proved to be a suitable combination to maximize system reliability. A chronological methodology based on Hongxing and Diaf techniques for optimal sizing of a Photovoltaic Wind Hybrid System (HPWS) (using batteries for energy storage) is presented. Accordingly, the purpose of this work is to help to promote the hybrid power system concept through a fully theoretical point of view. The model can be used to optimize the system configuration, minimizing Loss of Power Supply Probability (LPSP) and Annualized Cost of the System (ACS). The proposed methodology was used to design an isolated HPWS that meets the energy demand of 49 users at Ishiruwo settlement (located in the municipality of Uribia, State of La Guajira - Colombia). Results show that there is an inversely proportional behavior between the two objectives under evaluation. Likewise, the chosen solution with low cost and high reliability suggests that it is better to use a fully Photovoltaic System (PV), since wind-turbine cost is very high. Finally, it is clear that the cost of isolated systems has begun to gain importance due to its competitiveness when compared to other types of generation such as diesel, although more than 50% of its value lies in batteries and other components.