Water is a gift of nature and has been recognized as a basic human requirement for domestic, industrial and agricultural purposes where it plays a key role in the development of an economy and also for the well-being of a nation. Water is an abundant natural resource that covers three-quarters of the Earth's surface. History demonstrates the importance of water in the sustainability of life and the development of civilization since the origin and continuation of humanity is based on water. Figure 1 Global availability of fresh water Although the earth is largely covered with water, nearly 98% of the earth's water is salt water from the ocean where it maintains a salt content too high for the water to be considered fresh water drinking; it is instead called brackish water. Less than 1% of fresh water is actually within human reach, as presented in the world water table in the figure above. Since available fresh water is limited on earth, its demand is increasing day by day. The increase in the world's population, agricultural, industrial and domestic uses around the world contribute to the depletion and pollution of freshwater resources, where most clean water resources are rapidly depleting throughout the world. world due to human consumption. Global population growth leads to the assumption that two-thirds of the population will not have enough fresh water by 2025. Asia, for example, is developing a water shortage that is the result of a few factors, including the demand for food where 80% of the Asian population water resources necessary for that sector. The second factor stated by Arjun Thapan, ADB Senior Special Adviser to the President on Infrastructure and Water, in an interview with ABC Australia is quick to… middle of paper… any depletion of fossil energy, hydrocarbons pollution and environmental degradation as stated by Amitava Bhattacharyya in his article published in the International Journal of Environment and Sustainability. Solar energy has the greatest potential of all renewable energy sources as it is the best alternative heating energy source. Despite being inexhaustible, clean and universally available, the use of solar energy is however cheaper than the use of fossil fuels especially in those areas where water for daily use must be transported partly over very long distances and others energy sources are impossible. It can be used directly as thermal energy or it can be converted into electrical energy via photovoltaic (PV) conversion or via a solar thermal system. Therefore, it is classified into two categories known as direct and indirect solar energy.