**2. Hybrid Energy System Model**

The structure of the HES under analysis is shown in Figure 1. On one hand, the diesel generator represents the controllable power source able to provide energy under any circumstance. Thus, energy not supplied (ENS) is neglected. Due to the fact that the diesel generator has important operating costs related to fuel consumption and overhauling, the incorporation of the wind generator combined

with BESS and power converter allows us to reduce the number of operating hours of the diesel unit, reducing the operating costs of the whole system.

**Figure 1.** Hybrid energy system (HES) under study.

Besides the wind generator, BESS, power converter, and diesel generator, the dump load (not shown in Figure 1) allows us to consume all the energy surplus of the system in order to maintain the energy balance. This could occur when BESS reaches its maximum capacity and a high magnitude of wind power is available.

In the next sections, computational models of the wind generator, BESS, and diesel generator will be carefully described.
