Question

Introduction of renewable energy

1) Draw a schematic diagram of a passivesolar water heater and write in numbered steps how it works (2 marks) In what specific applications can solar water heater be used? (1 mark) Consider a solar water heater with a flat plate collector of area 6 m-positioned in a place where the solar irradiance is 800 W/m a) How much solar power reaches the collector? (1 mark) b) If the flat plate collector has 50% efficiency, how much solar power is absorbed by the water? (1 mark) C) If 0.01 kg per second of water flows through the collector, what will be change in temperature of the water? (Specific heat capacity of water=4.2 KJ kg-°C.) (2 marks)

Answer 1

taoks have Ans. Passive solal water heater System that takes solar thermal energy f transforms it to hot water without using any other form of energy. Solar water heating system include storage tank & sobor collector Passive solar water heaters are typically less expensive and are mone seliable. Two types of passive solar water heaters are :- fotogral collector - store pasive system Thermo syphon systems Working : Storage Tanks & Solar collectors: - Solar storesge additional out lett inlet connected to f from the collector. In two tank system, solar water heates pre-heats the water before it enters nventional water heater, back up heater is combined with solar storage in one tank. Sun facing collector heats wo. woorking fluid that passes es into storage system. These system use basic principles of green house effect to prodence heat. The whole idea is to trap some. fluid in place I leave sunlight through walls in order to heat inside. five basic collector of passive solar water heaters are :- Glazed flat plate collector plate liquid based solar collector Enguated tube collector REDMI NOTegch Alar heater Conn Ungirzed, flat collector To chor's Signature 48MP QUAD CAMERA

e Glazed flat plote collector :- Glazing frame aming inlet outlet connection Enchussen flow Absorber plate insulations کتاو There consist of insulated metal box with a or plastic cover to block absorber plate, boxis filled with air ar water when sun bits Obsorbez plates heat is transferred to third in box. Tube filled wates passes through liquid & absorb cheat with circulating Only difference is Collectra Vingbzed flest pleste collector :- there is no insulation. As a result, they provides lower tempy & they are mostly used for swimming pool heating and pre-heating of water for contact Hal sunlight liquid based solar collector Perform som same way with basic difference that thid heated is not actual fluid, instead. it is doiven through pipes which are connected exchanger O REDMI NOTE scle [ pass through womer 48MP QUAD CAMERA warter of heat tranefer fluid Heated water or heat tromater fluid coldwater hat werter hot water Tank Barking up heat elements heat 1 ام اين Teacher's Song

a vaccum Evacuated Tube collector : Gloss tubes form space to prevent Joss from centrele water tube - absorber Sun bits contrab tube to provides thermal powe Batch solar heater i Batch collector hot water bouse Bypass solare storage /back up water cold heater water supply integral collector storage system . 9t consists of one or more water tank inside box which allows sunlight to pass through Water tank is actually absorber which attract sunlight to warm water Bread box system ETS 1 Solar water heater applications: - Evacuated Tubes : can be more useful than volos collectors bes heating t cooling purpose in industria like pharmaceuticals and doug påpest lesthes E textile industry. It can operate at a range of tempo from medium to high for seler water heates, swimming poole, air conditiones 't solas cooker Swimming pools:- floating pool.covering system ase used for pool beatings Pool water is mildly Water is cusculated o REDMI NOTE 8 48MP QUAD CAMERA Clije to chlovice Teacher's site

DATE: 1 1 collector, through parmals using existing pool fitter. Collector pannels are mounted low tempo diffrenes b/w oir f water, pannels are nearby roof. Due to formed collector om unglazed that plate plate Solar irradiance soo w/m² @ Solar power reaching = 800 x 6 = 48oo w Given:- flat collector arrear 6m² 4boo W. collector Efficancy = 50%. solar power absoobed by water = 글 800x6 2 240 V specific heat of water = 4.2 KJ kegia e change in tempy of water = 4.2 kJ x o. of kg Tegie ie, 0.042 KJ /c/sec REDMI NOTE 8