**1. Introduction**

When something shifts in the cosmos, it also shifts in a quantity we call energy. Although its exact definition is unknown, the term "energy" is frequently used to ability of a physical or biological system to describe the motion or change. Movement, heating, and chemical transformation are just some of the various changes that can be brought about by applying different types of energy. Energy is required for all actions, including those performed by humans. It's necessary for humans to do activities like walk, cook, heat, and light their homes, and operate motor vehicles. Mankind is a voracious energy consumer. On average, a young man's daily energy needs amount to roughly 2500 kcal (2.9 kWh) while he is actively engaged in physical activity. An annual energy cost of roughly \$106 is implied. The present annual worldwide energy use is close to 20,000 kWh per person. If this trend continues, men will consume 19 times more energy than they need to maintain their current level of health and

well-being. Over the past 100 years, humanity has seen a significant growth in energy use. While the annual energy consumption per resident was approximately 5800 kWh in 1890, it increased to 20,200 kWh in 1970. Since 1970, the amount of energy used per resident per year has decreased to the current level of 19,000 kWh. The evolution process that began roughly five centuries ago can be linked to the rise in energy use in the twentieth century. The eighteenth century's Enlightenment saw the development of the philosophy of human progress, which provided the framework for this procedure. The method was intended to examine the environment and how it could be modified to better meet the needs of those whose lives would become safer and more comfortable. Growing industrialisation and mass production, which required an increasing amount of energy, went hand in hand with this process. Coal was the primary energy source at the end of the nineteenth century. During this time, electricity—a brand-new and sophisticated kind of energy—was introduced in the industrialised nations. This kind of energy was quickly used extensively. In the early twentieth century, as a result of the enormous rise in electricity demand and the subsequent building of hydroelectric plants, hydropower became a significant source of energy. At the close of the twentieth century, the oil and gas industries began to play a considerable part as contributors to the world's energy supply. Present-day energy sources are dominated by coal, oil, and gas. These three forms of energy (coal, oil, and gas), generally known as fossil fuels, are referred to as "conventional energy sources." During this time, nuclear energy was introduced as a brand-new energy source. Numerous household items are inexpensive because of growing and more efficient mass production. Given the tremendous increase in product consumption, it's not surprising that we now refer to modern society as a "consuming society." The quest for and use of new, sustainable energy sources has become a major issue near the end of the twentieth century. The urgency of this problem is highlighted by the Earth's finite supply of fossil fuels and rising global demand for energy generation. The focus is shifting to renewable energy sources because of this. Every human action requires energy. When considering the production and consumption of energy by human civilization, an energy system can be used to explain it. The population, overall energy consumption, and the types and sources of energy that people consume make up the key elements of the energy system. The energy system at the beginning of the twenty-first century is characterised by the six billion people who occupy the globe and the 1,300,000,000 kW of total energy use.

Even now, the cost of producing electricity from renewable sources is higher than that of conventional ones. As a result, it is not yet economically feasible in industrialised nations to use renewable energy sources as electricity power sources on a large scale. The main driver of a developing market for renewable energy sources and favourable national regulations is certainly their positive effects on the environment. But for the two billion people who, in many parts of the world, do not have access to an electricity grid, power generated from renewable energy sources is already the option that has the lowest overall cost.

The definition of "energy transition" is the move away from carbon-based energy sources during the coming years [1]. Therefore, it is crucial to provide energy using sources that can be regenerated organically over time on a human timeline. Renewable energy is the name given to this type of energy, which is largely environmentally safe and sustainable. Recent technological advancements have made it easy to convert various types of renewable energy into other forms of energy (such as electricity and heat).

As a direct consequence of this, in 2015 the international community came together to adopt the Sustainable Development Goals (SDGs) as a component of the United Nations 2030 Agenda for Sustainable Development [2]. The objectives promise to end malnutrition, poverty, etc. Some of the objectives specified by the world community, such as the provision of clean energy, climate protection, and others, were energy-related. The seventh goal (SDG-7) aims to raise the proportion of renewable energy in total energy by the year 2030 and to offer clean, cheap, and contemporary energy services in all parts of the world. In addition, Sustainable Development Goals−13 aims to enhance immunity either through increasing the resistance of a number of countries or by educating and raising awareness among the general public.

This is due to the fact that every nation on earth is susceptible to the repercussions of climate change. The vast majority of the energy that is required to keep things moving in the atmosphere comes from the sun. This energy is emitted in the form of electromagnetic waves, which have wavelengths ranging from 0.2 to 4 m and are invisible to the human eye. A photon is the smallest quantifiable unit of an electromagnetic field. The current definition of a photon is based on studies conducted by Albert Einstein between 1900 and 1920 (which were based on studies conducted by the German scientist Max Planck). Gilbert Lewis is credited with being the first person to use the term "photon," which was first published in Nature in 1926. Solar irradiance is the amount of energy that is received from the sun at a certain location and time in the form of electromagnetic radiation. This energy is measured in watts. It is stated as a number, and the unit of measurement used to determine it is W/ m2 . One of the most important forms of renewable energy is the sun's rays, which are collectively referred to as "solar energy" by the general public. There are two primary categories of technology that exist to capture the sun's rays: active solar technologies, such as photovoltaic systems, and passive solar technologies, which encompass a wide range of practises and may include orienting a building to the sun. Active solar technologies include photovoltaic systems. Passive solar technologies include a wide range of practises. Active solar technologies include photovoltaic systems.
