**2. Pertinent terms**

*Wind Solar Hybrid Renewable Energy System*

day and night times, unlike other renewable.

sun and is harnessed by human using technologies.

and incident solar irradiance level of 1000 W/m2

based on wind energy with a PV system.

this intermittent nature of renewable, single renewable energy source tends to be problematic in terms of energy yield and operational cost. Based on the aforementioned drawbacks, two or more renewable are being combined to form a hybrid renewable energy system (HRES). The main goal of doing this, or to improve electrical power production, to minimize cost, to reduce negative effects associated

In recent times, the integrated renewable energy system is gaining more attention, because a hybridized system can be efficiently applied to supply high efficiency and reliable electricity to the end-users, unlike a single-renewable source. A HERS can be applied in stand-alone or grid-connected modes. Stand-alone system must have a large storage to handle the load. While in a grid-connected mode, the storage can be small, and the deficient power can be acquired from the grid. It should be noted that, grid-connected mode must have a power electronic controllers for load sharing, voltage, harmonic, and frequency control. Thus HERS operating model is classified into Island mode where the generated electricity is consumed locally and grid connected mode where the renewable energy source is connected to the grid [5]. It is interesting, to note that, among the renewable energy sources, wind power is the fastest growing in terms of global annual and cumulative installed capacity. Wind energy is almost everywhere around the world. But the wind speed strength varies depending on the particular area. Wind energy can be operates during the

Solar is the cleanest and most abundant renewable energy source available on earth (SEIA 2013). Solar energy can be defined as radiant light and heat from the

.

Because of the aforementioned reasons, this chapter focuses on design, modeling, optimization, control and sensitivity analysis carried out on a hybrid system

The amount of energy harnessed from the sun is depending on radiation and scientists define radiation in two different ways which are energy in wave form (electromagnetic wave) or energy in particle form (photons). The electromagnetic radiation emitted from the sun has the wave length interval from 0.1 nm to 104 m. However, 95% of solar energy reach earth with the intervals of 0.3–2.4 μm only [5, 6]. The photons are traveling through space at the speed of 3.0 × 108 m/s and each photon carry different amount of energy measured in electron volts. Photovoltaic (PV) is derived from two words: photo which means light and voltaic or volt means the unit of electric potential. PV or solar cells, also called the semiconductor that converts sunlight to direct current (DC) electricity. PV cell is typically a thin wafer which consists of an ultra-thin layer of phosphorus-doped (N-type) silicon on top of a thicker layer of boron-doped (P-type silicon). The p-n junction is created through the doping and the electrical field is created near the top surface of the cell. When a sunlight which carries photons strike the PV cell, the current is produced because the photons prompt the electrons flow from n- to p-junction. A typical silicon PV cell will produce about 0.5 ~ 0.6 V under open-circuit condition regardless of size. The current produces is proportional to the intensity of sunlight striking the surface as well as the efficiency and size of the cell. The photovoltaic cell normally connected in series or parallel circuit to produce the desired amount of current. PV modules consist of PV circuits sealed in an environmentally protective laminate. PV module is the fundamental building blocks for a PV system. PV panels involve one or more PV module assembled as pre-wired, field-installable unit. Series of PV panels are called a PV array which is ready-installed unit for power generation. The performance of PV modules and array are basically rated according to their maximum power output (w) tested under Standard Test Conditions (STC). Standard Test Conditions are defined as a cell (module) operating temperature of 25°C (77°F)

with burning fossil fuels and to improve the overall system efficiency.

**96**

The terms are technical in nature and there brief explanations will go a long way to concept discussion the hybrid renewable energy power system characteristics, thus, optimization, reliability, grid, micro grid, macro grid, diverse generation, hybrid energy system, and hybrid renewable energy system.
