Comparative study on renewable stills

Problems for drinking water world faced a lot from water scarcity for drinking and cooking this book aims to identify the problems and give simple solutions to solve these problems. This will be useful to arid areas were many people will benefit. Water covers 70.9% of the earth's surface, and is vital for all known forms of life. On earth, 96.5% of the planet's water is found in oceans, 1.7% is in groundwater, and the remaining is in glaciers and the ice caps of Antarctica and Greenland leaving a small fraction in other large water bodies, and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Less than 0.3% of freshwater is in rivers, lakes, and the atmosphere, and an even smaller amount of the earth's freshwater (0.003%) is contained within biological bodies and manufactured products. Water on earth moves continually through the hydrological cycle of evaporation and transpiration, condensation, precipitation, and runoff, usually reaching the sea. Evaporation and transpiration contribute to the precipitation over land.