Introductory Chapter: Overview of Renewable Energy

*Ahmed M.A. Nahhas*

#### **1. Introduction**

This chapter presents an introductory review about renewable energies. Renewable energy is the most important resource of reproducible infinite energy [1]. There are major differences between renewable and regular energy resources. These differences include the diversity, availability, and potential everywhere. Moreover, renewable energy produces less carbon dioxide [2–4]. Renewable energy has several forms. These forms include solar, water, wind, geothermal, and biomass. Wind energy is produced from air and wind. It is produced due to the heat of the Earth's surface. The more the wind speed increases, the more energy is produced. On the other hand, the solar energy is produced from the sunlight. Special silicon cells are used to collect sunlight. The resulting collected energy is stored on batteries. Several types of batteries are used for storing solar energy. Biomass energy is another form of renewable energy. This type of energy is produced from biomaterials. Geothermal energy is produced from heat inside the earth [5, 6].

#### **2. Renewable energy technologies**

There are several technologies used for producing the renewable energy. These technologies include electrical and mechanical to produce heat and electricity. These technologies are used for hydro, solar, fuels, and geothermal energy [7]. Renewable energy resources are divided into several categories. These categories differ from country to country and from land to land. Different countries have different policies for the renewable energy categories. The political perspective of the policy maker in one country may be to justify different treatment for established resources such as large hydroelectric from nascent resources such as geothermal [8].

#### **3. Different types of renewable energy sources**

There are several types of renewable energy sources including:


#### **4. Renewable energy applications**

Renewable energy has several applications. These applications can be divided based on two categories: ON Grid and the OFF Grid. The ON Grid includes solar and wind energy [8, 9]. The OFF Grid includes biomass and geothermal energies. The most important factor for these two categories is the cost of connections and installations. The OFF Grid is used for homes and small businesses. On the other hand, ON Grid is used for cities and big factories. Moreover, a third category, mini Grid, is used for mixed applications [9].

## **5. Benefits of renewable energy**

The advantages of renewable energy are numerous and affect the economy, environment, national security, and human health. Some benefits include reliability, security, and resilience of power grid, job creation industries, and reduced carbon emissions and air pollution [9–11].

## **Author details**

Ahmed M.A. Nahhas Faculty of Engineering and Islamic Architecture, Department of Electrical Engineering, Umm Al Qura University, Makkah, Saudi Arabia

\*Address all correspondence to: amnahhas@uqu.edu.sa

© 2023 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

#### **References**

[1] Bhatia S, Gupta R. Renewable Energy. UK: WPI; 2018

[2] Sorensen B. Renewable Energy. Elsevier; 2017

[3] Twidell J, Weir T. Renewable Energy Resources. Taylor and Francis; 2015

[4] Alabdali Q, Bajawi A, Nahhas A. Review of recent advances of shading effect on PV solar cells generation. Sustainable Energy. 2020;**8**(1)

[5] Alzahrani G, Alzahrani F, Nahhas A. Study of the specific factors effecting the PV solar cell's efficiency in Saudi Arabia. Sustainable Energy. 2020;**8**(1)

[6] Alabdali Q, Bajawi A, Fatani A, Nahhas A. Review of recent advances in wind energy. Sustainable Energy. 2020;**8**(1)

[7] Alzahrani G, Nahhas A. Analytical study of power generation by photovoltaic system for Al-Riyadh and Al-Jubail regions in Saudi Arabia. American Journal of Energy Research. 2021;**9**(1)

[8] Alabdali Q, Nahhas A. Simulation study of grid connected photovoltaic system using PVsyst software: Analytical study for Yanbu and Rabigh regions in Saudi Arabia. American Journal of Energy Research. 2021;**9**(1)

[9] Bajawi A, Nahhas A. Analytical study of power generation using PV system for Al-Shuaiba and Al-Shuqiq regions in Saudi Arabia. American Journal of Energy Research. 2021;**9**(1)

[10] Albarrak A, Alshareef A, Alshareef A, Nahhas A. Review of hydrogen based fuel cells energy storage systems. Sustainable Energy. 2022;**10**(1)

[11] Jee A, Alsluimani J, Alqurashi A, Akkur A, Nahhas A. Review of recent advances of supercapacitors energy storage systems. Sustainable Energy. 2022;**10**(1)

Section 2
