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A PRESENTATION ON APPLICATIONS OF SOLAR ENERGY TECHNOLOGY, DESCRIBING VARIOUS SOLAR DEVICES ....

A PRESENTATION ON APPLICATIONS OF SOLAR ENERGY TECHNOLOGY, DESCRIBING VARIOUS SOLAR DEVICES ....

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    SOLAR ENERGY TECHNOLOGY SOLAR ENERGY TECHNOLOGY Presentation Transcript

    • 1 SOLAR ENERGY TECHNOLOGY VANITA THAKKAR ASSOCIATE PROFESSOR, MECHANICAL ENGINEERING DEPARTMENT, BABARIA INSTITUTE OF TECHNOLOGY, VARNAMA, VADODARA VANITA THAKKAR
    • 2 LIMTATIONS OF CONVENTIONAL ENERGY SOURCES Growing scarcity due to limited Resources. Ever increasing cost. Fear of possible environmental risks. VANITA THAKKAR
    • 3 Type of facility Lead time (Years from decision to start up ) Nuclear plants 8-10 Coal or Oil fired power plants 5-7 Hydroelectric plant 20 Geothermal power plant 5 Gas turbine power plant 2 New coal mine 3-6 New off-shore oil field 2-4 Shale oil plant 5 Liquefaction plant 5 WHY SOLAR ENERGY TECHNOLOGY ? – CONTEXT – LEAD TIME VANITA THAKKAR
    • SOLAR ENERGY UTILIZATION SOLAR DEVICES DIRECT CONVERSION SOLAR THERMAL CONVERSION SYSTEMS SOLAR PHOTOVOLTAICS FLAT PLATE COLLECTORS CONCENTRATING COLLECTORS 4VANITA THAKKAR
    • 5 Transfer of solar radiant energy on to the electrons of a solid in :  Photovoltaic cells  Photogalvanic cells : applied to photolysis of water.  Phototubes : Electrons are emitted from the cathode under illumination may also serve to generate power. DIRECT CONVERSION OF SOLAR ENERGY VANITA THAKKAR
    • 6 Conversion of radiation energy into heat and secondarily into electricity in a thermodynamic process.  Flat plate solar collectors  Concentrating solar collectors  Solar Tower  Solar Chimney etc. INDIRECT CONVERSION OF SOLAR ENERGY VANITA THAKKAR
    • 7 TECHNOLOGY SELECTION VANITA THAKKAR
    • 8 SOLAR RESOURCES WORLDWIDE VANITA THAKKAR
    • 9 THE WORLD’S SUN BELT VANITA THAKKAR
    • 10 ENERGY FROM SUN  The Sun generates energy at the rate of 3.8x1023 kW.  Earth receives only a small part of it, but that is also considerable.  Earth receives 1.7x1014 kW or 5.3×1024 J / year of solar energy  8.4 × 1023 J / year reaches the surface of Earth.  Current world consumption of energy is 4.0 × 1020 J / year from all sources.VANITA THAKKAR
    • 11 ENERGY FROM SUN (contd.) • All chemical and radioactive polluting byproducts of the thermonuclear reactions remain behind on the sun, while only pure radiant energy reaches the Earth. • Energy reaching the earth is incredible. By one calculation, 30 days of sunshine striking the Earth have the energy equivalent of the total of all the planet’s fossil fuels, both used and unused ! VANITA THAKKAR
    • 12 KEY FEATURES OF SOLAR ENERGY • It is the most promising renewable source of energy. • It is an essentially inexhaustible source of energy. • It has potential to meet a significant portion of the nation’s future energy need because of its quantitative abundances. • It is clean and environment friendly source of energy. VANITA THAKKAR
    • 13 LIMITATIONS OF SOLAR ENERGY • It is diluted source of energy. • Its availability varies widely with time. • It needs storage system.VANITA THAKKAR
    • 14 Solar Radiation Load Contact grid 14 SOLAR PHOTOVOLTAICS VANITA THAKKAR
    • 15 Photovoltaic effect :  The direct conversion of sunlight into electric power is achieved by semi-conductor effect – valence electrons get freed by the energy gained from incident sunlight – in solar cells.  A Photovoltaic conversion effect can be achieved in all semiconductors.  Most of the cells are manufactured from monocrystalline material. SOLAR PHOTOVOLTAICS (contd.) VANITA THAKKAR
    • 16 New technological approaches : The thin cell • A decrease in the consumption of material per unit of power generation. • The avoidance of sophisticated metallurgy, namely mono-crystalline material and ultra-high purity (often called electronic grade material). • These technologies are suitable for a continuous production process. SOLAR PHOTOVOLTAICS (contd.) VANITA THAKKAR
    • SOLAR PHOTOVOLTAICS (CONTD.)  The fundamental power unit of a PV system is a solar cell.  It is a semi conductor generally made of silicon.  A solar cell is a thin wafer , which is chemically treated and processed at high temperature .  Many such wafers are joined together to create a p-n junction, across which voltage develops when sunlight falls on these cells .  There are four common types of silicon photovoltaic cell :-  Single crystalline silicon  Poly crystalline silicon  Ribbon silicon  Amorphous silicon e- N-TYPE JUNCTION JUNCTION ZONE P-TYPE SILICON e- V17VANITA THAKKAR
    • Solar photovoltaic panel :- when many cells are connected in series to increase the voltage. Several series of cells can be interconnected in parallel to increase the power output. Solar cells are extremely fragile , so to protect them from damage, they are sealed on the top by a layer of glass and bottom with a layer of plastic or a metal or a combination of the two . The SPV panels are rated in terms of peak watt units – which means minimum no. of hours of sunlight required to produce a desirable amount of electricity daily. SOLAR PHOTOVOLTAICS (SPV) (contd.) 18VANITA THAKKAR
    • SOLAR LANTERN  Solar lantern is a single light point portable system.  Apart from the PV panel , it consists of Lamp Battery Electronic components All placed in a casing , either made of metal plastic or fibre glass .  Due to portability, it is found in both indoors and outdoors applications . CFL LANTERN 19VANITA THAKKAR
    • Battery  A sealed maintenance free, lead–acid battery or a tubular plate lead acid battery with spill proof feature is used . PV panel  A PV panel typically has a power rating of 12 volts . Electronic component  Invertors with at least 80 percent efficiency is provided with system .  Solar lantern are also provided with two led indicators to indicate charging and deep discharge state. SOLAR LANTERN (contd.) 20VANITA THAKKAR
    • 21VANITA THAKKAR
    • 22VANITA THAKKAR
    • 23 SOLAR PHOTOVOLTAICS (contd.) VANITA THAKKAR
    • 24VANITA THAKKAR
    • 25VANITA THAKKAR
    • 26VANITA THAKKAR
    • 27VANITA THAKKAR
    • 28 SOLAR COLLECTORS OR SOLAR THERMAL SYSTEMS Solar Radiation Load Thermal Storage Auxiliary Air blower Solar Collector VANITA THAKKAR
    • 29 SOLAR THERMAL HEAT  Solar cookers – Domestic and Community type.  Solar Architecture – Active and Passive  Medium temperature for water heating  Solar heated swimming pool  Crop drying and Industrial process heat – Pharmaceuticals, Dairies, Textile industries, Food Processing Units, etc.  Solar Thermal Power Plants VANITA THAKKAR
    • VANITA THAKKAR 30 Energy conversion chain of solar thermal power generation SOLAR THERMAL POWER PLANTS
    • 31 SOLAR THERMAL POWER PLANTS VANITA THAKKAR
    • VANITA THAKKAR 32 SOLAR THERMAL POWER PLANTS Vertical tube receivers using salt as heat transfer medium
    • 33VANITA THAKKAR SOLAR THERMAL POWER PLANTS (contd.)
    • 34 SOLAR TOWER VANITA THAKKAR
    • VANITA THAKKAR 35 DISH TECHNOLOGY WITH STERLING CYCLE POWER GENERATION
    • 36 DISH TECHNOLOGY WITH STERLING CYCLE POWER GENERATION VANITA THAKKAR
    • 37 VANITA THAKKAR
    • 38VANITA THAKKAR
    • 39 SOLAR THERMAL CHIMNEY The solar updraft tower or Solar Chimney is a proposed type of renewable-energy power plant in which air is heated in a very large circular greenhouse-like structure, and the resulting convection causes the air to rise and escape through a tall tower. The moving air drives turbines, which produce electricity. VANITA THAKKAR
    • 40 VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • 41 Key features:  The generating ability of a solar updraft power plant depends primarily on two factors: 1. Size of the collector area : With a larger collector area, more volume of air is warmed up to flow up the chimney; collector areas as large as 7 km in diameter have been considered. VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • 42 Key features (contd.): 2. Chimney height : With a larger chimney height, the pressure difference increases the stack effect; chimneys as tall as 1000 m have been considered.  Further, a combined increase of the collector area and the chimney height leads to massively larger productivity of the power plant. VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • 43 Key features (contd.):  Heated air, being less dense, raises in tall tower / chimney.  Thermal source from ground based thermal collector around : Heat can be stored inside collector area greenhouse, to be used to warm air later on. Water, with its relatively high specific heat capacity, can be filled in tubes placed under collector increasing energy storage as needed. VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • 44 Key features (contd.):  A small-scale solar updraft tower may be an attractive option for remote regions in developing countries. The relatively low-tech approach could allow local resources and labour to be used for its construction and maintenance. VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • 45 The chimney had a height of 195 metres and a diameter of 10 metres, with a collection area (greenhouse) of 46,000 m² (about 11 acres, or 244 m diameter) obtaining a maximum power output of about 50 kW. VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • 46 Based on the test results, it was estimated that a 100 MW plant would require a 1000 m tower and a greenhouse of 20 Sq. km. As the costs lie mainly in construction and not in operation (free 'fuel', little maintenance and only 7 personnel), the cost per energy unit is largely determined by interest rates and years of operation. VANITA THAKKAR SOLAR THERMAL CHIMNEY (CONTD.)
    • SPACE REQUIREMENT FOR VARIOUS SOLAR THERMAL POWER PLANTS VANITA THAKKAR 47
    • SOLAR COLLECTORS  Solar collector - the most important component – form heart of the Solar Energy Collection Systems : 70-90 % of the system cost.  Solar collector- intercepts, absorbs and transforms solar radiations into a usable form. Solar collector can be :- WATER HEATING COLLECTOR OR AIR HEATING COLLECTOR and each of these collectors can be :- FLAT PLATE COLLECTOR OR FOCUSSING COLLECTOR. 48VANITA THAKKAR 48
    • SOLAR FLAT PLATE COLLECTORS The flat plate collector forms the heart of many solar energy collection systems. It is designed for operation in low temperature range from, ambient to 600 C, or medium temperature range, from ambient to 1000 C. 49VANITA THAKKAR
    • SOLAR FLAT PLATE COLLECTORS (contd.) PRINCIPLE:  If a metal sheet is exposed to solar radiation, its temperature will rise, until the rate at which energy is received is equal to the rate at which heat is lost from the plate (this temperature is termed as the ‘equilibrium temperature’.)  If the back of the plate is protected by a heat insulating material, and the exposed surface is painted black and is covered by one or two glass sheets, then the equilibrium temperature will be much higher than that for the simple exposed sheet and heat can be stored and transferred to the working medium. 50VANITA THAKKAR
    • 51 SOLAR WATER HEATING COLLECTOR Tube Insulation Water in Blackened Absorber plate Glass cover Solar Radiation 51 VANITA THAKKAR
    • 52 VANITA THAKKAR SOLAR WATER HEATING COLLECTOR
    • Pictures Flat plate solar heater Flat plate over roof 53VANITA THAKKAR
    • ADVANTAGES OF FLAT PLATE COLLECTORS : Absorb direct, diffused and reflected components of solar radiation Are fixed in tilt and orientation and, thus, there is no need of tracking the sun. Are easy to make and are low in cost. Have comparatively low maintenance cost and long life. Operate at comparatively higher efficiency. 54VANITA THAKKAR
    • MATERIALS FOR FLAT PLATE COLLECTORS: Absorber plate: It should have: high thermal conductivity. adequate tensile and compressive strength. good corrosion resistance. Copper is generally preferred. Other materials are Aluminium, steel and various thermoplastics. 55VANITA THAKKAR
    • Insulation :  Several insulating materials which can be used to reduce the heat loses are available – such as, glass wool, etc.  Desired characteristics of these insulating material are :  Low thermal conductivity.  Stability at high temperature (upto 200oC).  No degassing upto around 200oC.  Self supporting feature without any tendency to settle.  Ease of application.  No contribution to corrosion. MATERIALS FOR FLAT PLATE COLLECTORS (contd.) : 56 VANITA THAKKAR
    • Cover plate :  Characteristics of cover plates through which solar energy is transmitted are extremely important in the functioning of a collector.  Functions of the cover plate are :-  To transmit maximum solar energy to absorber plate .  Minimize upward heat loss from the absorber plate to the environment .  To shield absorber plate from direct exposure to weather.  Other factors such as strength, durability, non- degradability are important . MATERIALS FOR FLAT PLATE COLLECTORS (contd.) : 57 VANITA THAKKAR
    • THE LIQUID FLAT PLATE COLLECTOR: BASIC COMPONENTS :  Flat absorbing plate, normally Metallic upon which the short wave Solar radiation falls and is absorbed.  Tubes, channels or passages attached to the absorber plate to FLAT PLATE COLLECTOR circulate the liquid required to remove the thermal energy from the plate  Thermal insulation provided at the back and sides of the absorber plate to minimize the heat losses  A transparent cover of glass or transparent plastic to reduce the upward heat loss from the absorber plate  A weather-tight container to enclose the above components. 58 VANITA THAKKAR
    • CLASSIFICATION OF FLAT PLATE COLLECTORS (According to applications) :  Simple and low cost collectors with no cover and insulation. e.g. for heating swimming pools where less heat is required.  Collectors with low cost insulation and one transparent cover e.g. in areas requiring domestic water heating.  Well engineered and sophisticated flat plate collectors for process heating or small-power production. 59 VANITA THAKKAR
    • CLASSIFICATION OF ABSORBER PLATES Pipe and fin type, in which the liquid flows only in the pipe, and hence has comparatively low wetted area and liquid capacity. Rectangular or cylindrical full sandwich type in which both the wetted area and the water capacity are high. Roll bond type or semi-sandwich type, intermediate between type I and II. 60 VANITA THAKKAR
    • Pictures Basic collector absorber plate types Flat plate solar heater for swimming pools 61 VANITA THAKKAR
    • Can be of two types : A FLAT PLATE COLLECTOR OR A FOCUSSING COLLECTOR AIR HEATING COLLECTORS  Solar energy air collectors are special kind of heat exchangers that transform solar radiation energy into internal energy of air. 62 VANITA THAKKAR 62
    • 63 FLAT PLATE SOLAR AIR COLLECTOR 63VANITA THAKKAR
    • DESIGN VARIATIONS OF SOLAR AIR COLLECTOR Collector with side reflector Reflector Absorber Insolation 64 VANITA THAKKAR 64
    • Collector with multiple glass cover Collector with selective absorber plate Double exposure air collector Top glass cover Top absorber plate Stagnant air gap Bottom absorber plate Bottom glass cover Air Air Air 65 VANITA THAKKAR 65
    • Collector with corrugated absorber Corrugated absorber plate Bottom plate Air flow channel 66 VANITA THAKKAR 66
    • Jet Plate air collector Clear glass Absober plate Jet plate Bottom plate Insulation Air in Air out 67 VANITA THAKKAR 67
    • Overlapped glass plate air collector Flow Straightener Clear glass Glass cover Blackened glass Insulation Air in Air out 68 VANITA THAKKAR 68
    • Evacuated glass tube collector Structural foam body Fiber mat absorber Evacuated tube 69 VANITA THAKKAR 69
    • Absorber plate made of recyclable aluminium cans Honeycomb solar air collector Air out Honeycomb structure Glass cover Insulation Air in 70 VANITA THAKKAR 70
    • 71 Collector with box type absorber Artificially roughened solar air collector Glass cover Roughened surface Air in Air out Air flow channel VANITA THAKKAR
    • Collector with fins on absorber plate Glass cover Multiple transmission & absorption Air flow Insulation Air in Air out 72 VANITA THAKKAR 72
    • 73 Two pass solar air collector First glass cover First air pass Second glass cover Second air pass Absorber plate Insulation 73 VANITA THAKKAR
    • 74 Collector with metal matrix absorber (packed duct collector) Air in Air out Air out Air in Air in Air outSolar radiation Solar radiation Solar radiation Matrix Matrix Matrix 74 VANITA THAKKAR
    • 75 EFFECT OF PARAMETERS ON PERFORMANCE System parameters Number of glass cover Glass cover emissivity Selectivity of absorber plate Plate spacing Collector tilt Operation Parameters Inlet fluid temperature Mass flow rate Meteorological Parameters Incident Solar radiation Ambient temperature Wind velocity Dust on the top glass cover 75 VANITA THAKKAR
    • 76 PERFORMANCE ENHANCEMENT METHODS 76VANITA THAKKAR
    • SOLAR COOKERS  As the supply of fossil fuels like coal, kerosene or cooking gas is deteriorating, more and more solar energy is harnessed for cooking purposes. THREE BASIC DESIGNS OF SOLAR COOKER:-  FLAT PLATE BOX TYPE SOLAR COOKER  MULTI REFLECTOR TYPE SOLAR OVEN  PARABOLIC DISC CONCENTRATOR TYPE SOLAR COOKER 77VANITA THAKKAR
    • FLAT PLATE BOX TYPE SOLAR COOKER It consists of a solar box of size usually 60 cm x 60 cm x 20 cm.  It is made up of inner and outer metal or wooden box with double glass sheet on it.  Absorber tray is painted black with dull color so that it can withstand maximum temperature attained inside the cooker as well as water vapour coming out of cooking utensils. 78VANITA THAKKAR
    • FLAT PLATE BOX TYPE SOLAR COOKER (contd.) Top cover contains 2 plain glasses 3mm each, fixed in wooden frame with 20 mm distance between them.  Neoprene rubber sealing is provided around contact surface of glass cover and cooker box. A small vent is provided in sealing for vapour escape.  On one side of glass frame, plane reflecting mirror is hinged, which remains perpendicular to the box while cooking and is equal in size to the box, to form its cover during closed condition. 79VANITA THAKKAR
    • MULTI REFLECTOR TYPE SOLAR OVEN The solar oven consists of a well insulated semi- cylindrical box made of aluminum sheet and wood.  Two shells are made and the space between them, about 7.5 cm, is filled with fibre glass insulation. The interior sheet is painted black.  A door of the same insulating material is also made for keeping and taking out food. 80VANITA THAKKAR
    • MULTI REFLECTOR TYPE SOLAR OVEN (contd.) The window (40 X 40 cm) of the oven consists of two transparent glass sheet (3 mm thk.) with a spacing of 2 cm.  Eight reflectors made of silvered glass mirrors, four of square shape and four of triangular shape are typically used.  The oven can be manually tilted and oriented towards the sun. With single reflector, temperature attained reaches upto 160o and in multi- reflector it reaches around 200o to 250o. 81VANITA THAKKAR
    • PARABOLIC DISC CONCENTRATOR TYPE SOLAR COOKER  Parabolic disc is used in this type of solar cooker.  Solar radiations are concentrated at a point, focus.  Cooking pot is placed at this point where a very high temperature is maintained, about 450 deg Celsius. Wall Reflector Solar Cooker 82VANITA THAKKAR
    • Pictures Reflective Cooker Inclined box type cooker Box type solar cooker Inclined Solar Cooker 83VANITA THAKKAR
    • ADVANTAGES OF SOLAR COOKERS :  No attention is needed in cooking as in other devices.  No fuel is required.  Negligible maintenance cost.  No pollution.  Vitamins of food are not destroyed and food cooked is nutritive and delicious with natural taste.  No problem of charring of food and no over flowing. 84VANITA THAKKAR
    • DISADVANTAGES OF SOLAR COOKER  One has to cook according to the sun shine.  One can not cook at short notice and food can not be cooked in the night or during cloudy days.  It takes comparatively more time.  Chapattis are not cooked because high temperature for baking is required and also needs manipulation at the time of baking. 85VANITA THAKKAR
    • SOLAR STILL A solar still is a low-tech way of distilling water, powered by the heat of the sun (more precisely, the heat & humidity of the soil, and relative cool of the plastic – in case of pit stills). Two basic types of solar stills are :  box stills : more sophisticated.  pit stills. VANITA THAKKAR 86
    • SOLAR STILL – PIT STILL • Impure water is contained outside the collector, where it is evaporated by sunlight shining through clear plastic. • The pure water vapour (and any other included volatile solvent) condenses on the cool inside plastic surface and drips down off of the weighted low point, where it is collected and removed. VANITA THAKKAR 87
    • SOLAR STILL – BOX STILL • The basic principle : It replicates the way nature makes rain. • The sun's energy heats water to the point of evaporation. VANITA THAKKAR 88
    • SOLAR STILL – BOX STILL • As the water evaporates, water vapor rises, condensing on the glass surface for collection. • This process removes impurities such as salts and heavy metals as well as eliminates microbiological organisms. The end result is distilled water. VANITA THAKKAR 89
    • SOLAR STILL – BOX STILL (contd.) • Solar stills use natural evaporation and condensation, which is the rainwater process. • This allows for natural pH buffering that produces excellent taste as compared to steam distillation. • They can be used to effectively remove many impurities ranging from salts to microorganisms and can even be used to make drinking water from seawater. VANITA THAKKAR 90
    • SOLAR STILL – BOX STILL (contd.) • Simple construction • No moving parts. • Material : which can withstand conditions produced by water and sunlight. • Operation : Simple – – water is added (either manually or automatically) through the still's supply fill port. – Excess water drains out of the overflow port, which keeps salts from building up in the basin. – Distilled water is collected from output collection port. VANITA THAKKAR 91
    • • Solar still has a top cover made of glass, with an interior surface made of a waterproof membrane. • This interior surface uses a blackened material to improve absorption of the sun's rays. • Water to be cleaned is poured into the still to partially fill the basin. • The glass cover allows the solar radiation (short-wave) to pass into the still, which is mostly absorbed by the blackened base. VANITA THAKKAR 92 SOLAR STILL – BOX STILL (contd.)
    • • Water begins to heat up and the moisture content of the air trapped between the water surface and the glass cover increases. • The base also radiates energy in the infra-red region (long-wave) which is reflected back into the still by the glass cover, trapping the solar energy inside the still ("greenhouse" effect). • Heated water vapor evaporates from basin and condenses on the inside of the glass cover. In this process, salts and microbes that were in original water are left behind. Condensed water trickles down inclined glass cover to an interior collection trough and out to a storage bottle. VANITA THAKKAR 93 SOLAR STILL – BOX STILL (contd.)
    • SOLAR POND VANITA THAKKAR 94 • A solar pond is a pool of saltwater which acts as a large-scale solar thermal energy collector with integral heat storage for supplying thermal energy. • A solar pond can be used for various applications, such as process heating, desalination, refrigeration, drying and solar power generation.
    • Intermediate insulating layer : has a salt gradient, which establishes a density gradient that prevents heat exchange by natural convection. Bottom layer : has a high salt content. If water is relatively translucent and pond's bottom has high optical absorption, nearly all of incident solar radiation goes into heating bottom layer. VANITA THAKKAR 95 SOLAR POND (contd.) There are 3 distinct layers of water in solar pond: Top layer : has a low salt content.
    • SOLAR POND (contd.) • When solar energy is absorbed in water, its temperature increases, causing thermal expansion and reduced density. • If water is fresh, the low-density warm water floats to the surface, causing a convection current. • The temperature gradient alone causes a density gradient that decreases with depth. • However, salinity gradient forms a density gradient that increases with depth, and this counteracts temperature gradient, thus preventing heat in lower layers from moving upwards by convection and leaving the pond. VANITA THAKKAR 96
    • SOLAR POND (contd.) • This means that the temperature at the bottom of the pond will rise to over 90 °C while the temperature at the top of the pond is usually around 30 °C. • A natural example : Solar Lake in the Sinai Peninsula of Egypt. • The heat trapped in the salty bottom layer can be used for many different purposes, such as the heating of buildings or industrial hot water or to drive an organic Rankine cycle turbine or Stirling engine for generating electricity. VANITA THAKKAR 97
    • SOLAR POND (contd.) Advantages and Disadvantages : • Particularly attractive option for rural areas in developing countries. Very large area collectors can be set up for just cost of clay or plastic pond liner. • Evaporated surface water needs to be constantly replenished. • The accumulating salt crystals have to be removed and can be both a valuable by-product and a maintenance expense. • No need of a separate collector for this thermal storage system. VANITA THAKKAR 98
    • SOLAR POND (contd.) VANITA THAKKAR 99 Plant diagram of a solar pond power plant
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    • 105 Range of conversion technologies, Energy devices and other technological interventions Sr. No Applications Technologies/Devices 1 Cooking  Use of Biogas plants  Use of improved and efficient chulhas  Use of Pressure cookers  Use of high efficient burners with LPG  Use of solar cookers  Use of solar water heaters 2 Lighting  Use of photovoltaic conversion  Use of switch from conventional to renewable 3 Power generation  PV power packs  Solar thermal power plants  Biomass gasifiers options  Biogas engine gensetsVANITA THAKKAR
    • 106 Sr. No Applications Technologies/Devices 3 Agriculture and Allied activities  Switch from incandescent lamps to CFL  Electronic ballast in place of Electro-magnetic ballast  Switch from diesel to electric motor pump  Rectification of existing pump and other devices  Biomass gasifiers based pumping system Solar PV pump sets Solar dryers 4 Rural Industry Improved biomass conversion system for thermal needs Increase availability of electricity Small cogeneration systems Use of more renewable sources 5 Transport and Basic amenities/ Facilities Improved bullock cart design PV street light PV power TV sets/tape recorder/transistors etc. PV refrigeration Solar water heating system Solar and passive architecture in residential, educational and community buildings. Community solar cookers for mid-day meal schemes etcVANITA THAKKAR
    • 107 THANK YOU VANITA THAKKAR
    • 108VANITA THAKKAR