No abstract

The main objective of the work was to use solar energy for desalination of water. A solar chimney desalination system, which includes the solar chimney, solar collector, evaporation system, and passive condenser, was designed and built. The air enters into collector and gets heated and released at the bottom of chimney. Due to draught effect dry air goes upward. The air is humidified by spraying salt water into the hot air stream using a mistifier at the middle of chimney. Then, the partial vapours contained in the air are condensed to give desalinated water. The performance of the integrated system including power and potable water production was estimated and the results were discussed. With a 3.4 m height setup, experimental test rig was capable of evaporating 3.77 L water daily condensing 2.3 L water. It is compact in nature as it is easy to assemble and dissemble. It can be used for purifying rain water in summer under rain water harvesting. Because of using country wood, recycled Al cans, and GI sheet in fabrication, it is lower in cost.

The main objective of solar air heater (SAH) is to make use of the solar potential for heating air and this is used for drying, crops, fishes, wet grains during post harvesting, space heating and in greenhouses. SAH is a black body which has less emissivity and high heat absorbing capacity. The air enters into the collector gets heated with addition of solar radiation. The collector is placed at an angle due to which the natural draught occurs. The main advantage of this type of air heater is compactness, maintenance, easy to assemble and dissemble. In this work a SAH is examined with the use of different materials, sizes and shapes (like plane, rugged) of absorber plates with optimum tilt angle for better thermal storage performance and greater efficiency.

Farmers are backbone of India and they suffer many hurdles while growing crops. In post-harvesting steps, drying crops plays a major role in grain production. About 70% of the threshed grains are sun-dried in many regions. During sudden rains farmers face difficulty to cover the threshed grains and some of them die because of thunderstorm/lighting with this older methods. It necessitates to design a new system for these conditions instead of older methods. The aim of the project is to provide an innovative design for helping farmers from unseasonal rains easily. The newly modelled Rain Sensor Capsule for farmers, whose operation is compiled by the automatic rain sensor, wooden capsule, controllers and power conversion unit. The capsule is modelled in AutoCAD software package, then a prototype is fabricated and tested.