2 Renewable Energy: Overview, Opportunities and Challenges

      The path toward achieving sustainable development goals necessarily pass by the integration of Renewable Energy Sources (RES) as the key factor for socio‐economic growth and improved public health. Contrary to traditional sources, i.e. fossil fuel and coal, the energy inexhaustibility and fast replenishment of RES gathered the attention of research community and stakeholders to promote the use of RSE to meet the ever‐growing demand for electricity. With the growing interest in RES, the incorporation of RES in the bulk power system has led to an inherent dynamic characteristic evolution in energy systems. This chapter provides a systematic review of the actual state of RES implementation, the challenging problems and the direction of future research. Furthermore, the operational integration of RES in the smart grid (SG) environment is also extensively discussed and included in this chapter.

2.1 Introduction

      The increasing damage and rapid depletion of traditional energy sources compel the worldwide population to achieve the necessary transition toward RES. It is vital that RES are included in the energy mix, especially, with an average growing rate of 1.8% energy consumption per year [1]. Existing electric power systems rely on fuel and coal to generate energy. The escalating permeation of RES aims to satisfy the expected global energy demand increase and the global energy demand to a large extant in order to meet the world's energy demand growth [2].

As a result of some environmental issues, a number of related organizations have engaged in research to increase efficiency and green power plants using developed technology. Concerns regarding environmental protection are rising, RES is therefore sought and examined. Fossil fuel and renewable energy costs, social and environmental prices are going in different directions and the economic and policy plans required to aid the extensive spreading of sustainable markets for renewable energy systems are developing quickly. Future growth in the energy sector will mainly be in the new regime of renewables. Hence, the transition to renewable energy can support us in meeting the challenges of decreasing greenhouse gas emissions, hindering future extreme weather and climate effects, and maintaining a reliable, timely, and cost‐efficient delivery of energy. The integration of renewable energy may result in substantial dividends for the future of energy security.

      Renewables, with nuclear and hydroelectric power, deliver 50% of the extra energy needed out to 2035. Furthermore, renewable energy is the fastest growing source of energy as a result of decreasing capital costs coupled with rising penetration and due to the present state and federal policies investing in its employment, with its share in the primary energy rising to 10% by 2035, up from 3% in 2015. In addition, renewables account for 40% of the increase in power generation, making their share of global power rise from 7% in 2015 to approximately 20% by 2035 [3, 4].

RES is helped by nature and produce energy straight from the sun (thermal, photo‐chemical, and photo‐electric), indirectly from the sun (wind, hydropower, and biomass), or from other natural phenomena of the environment (geothermal and tidal energy). Renewable energy does not include energy resources originating from fossil fuels, waste products from fossil sources, or waste products from inorganic sources [5]. Renewable resources are gained from solar energy, wind, falling water, the heat of the earth (geothermal), plant materials (biomass), waves, ocean currents, temperature differences in the oceans and the energy of the tides. Renewable energy technologies