Solar water heater: A solar water heater consists of a collector, pipes and an insulated tank. The collector is made of glass tubes in the evacuated vacuum tube system or metallic tubes in a flat plate collector system. It gets heated in sunlight and the heated water reaches the top of a water tank. The relatively colder and denser water descends into the tubes and gets heated through a continuous Thermo-siphon cycling effect. A 100 LPD water heater provides 100 liters of hot water at 65°C and saves Rs. 5000 energy costs annually. The existing design needs a change in terms of mechanism, size, and compactness. Solar power enables water purifier is expected to be attached with tube wells in the urban and rural zone to ensure the supply of clean purified drinking water.
Solar Charging for Computing Devices and Mobile Phones: Solar charging of batteries has recently become very popular for laptops, tablets, and mobile phones. The typical voltage output of a solar cell is 0.7 V. A solar panel may have eight cells connected in series producing 5.6 V at most. It can charge a single Li-ion battery used in cell phones to 4.2 V with a buck or step-down charger. It requires a boost step-up charger to charge a multicell Li-on battery of a laptop.
Solar Water Pumps for Agriculture: Let us analyze the technology of solar water pumps [58,59]. What is a solar pump and how is it different from conventional pumps? What are the various types of the solar water pump? What are the differences between surface and submersible pumps? Is a DC pump more efficient than AC pump? What are the advantages? What are the disadvantages such as the impact of cloudy and foggy days and natural disaster? What are the basic working principles, irrigation capacity, and average discharge? What is the procedure of site selection, erection, testing, and commissioning and relocation procedures of the solar pump? What is the outcome of cost-benefit analysis? What are the marketing, promotion, advertising, sales, and distribution strategies? What are the outcomes of technology life-cycle analysis?