ANAND INTERNATIONAL COLLEGE OF ENGINEERING

ANANDINTERNATIONAL COLLEGE OF ENGINEERINGPresentation onSOLAR ENERGY

Submitted by:KAILASH CHAND KUMAWATCollege ID: 11ME041

Submitted to:Department Of Mechanical EngineeringAnand International College Of EngineeringJaipur-303012WHAT IS SOLAR ENERGY?It is the radiation from the sun that is capable of producing heat, causing chemical reactions, or generating electricity.

It is the largest source of energy received on Earth, but its intensity on the earths surface is quite low.

Solar energy is rapidly becoming the ultimate energy source because of its non-polluting character and its inexhaustible supply which are in stark contrast to such fossil fuel sources as coal, oil, and natural gas.

HOW SOLAR ENERGY IS USED?We can use solar energy by converting it to electrical energy . So we must use a device called solar panels which can convert the light energy into electrical energy.

Solar panel is a group of solar cells.

Solar cells works on the principle of Photoelectric Effect. Photoelectric Effect is when a light of certain frequency falls on the surface of a metal , electrons will absorb the energy . If incident light energy is greater than the work function(minimum energy required to remove the loosely bound valence electrons)of the metal ,then the photo electrons will be emitted and the excess energy is converted to the kinetic energy of electron.

SOLAR CELL A solar cell (also called photovoltaic cell or photoelectric cell) is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. Assemblies of cells are used to make solar modules, also known as solar panels. The energy generated from these solar modules, referred to as solar power, is an example of solar energy.

Cells are described as photovoltaic cells when the light source is not necessarily sunlight. These are used for detecting light or other electromagnetic radiation near the visible range, for example infrared detectors, or measurement of light intensity.

WORKING OF SOLAR CELLSWhen solar panels are placed in the sunlight , photons will strike the surface and emits electrons.As a result electron hole pair is created in the solar cell.When external circuit is connected to the solar cell , electrons flow in the circuit and the current is generated.

APPLICATIONSHeatersGreen housesCarsWater pumpsLightsDesalinationSatellitesChillingDryersSolar pondsCalculatorsThermal Commercial use:On an office building , roof areas can be covered with solar panels.Remote buildings such as schools , communities can make use of solar energy.In developing countries , this solar panels are very much useful.Even on the highways , for every five kilometres ,solar telephones are used.

Solar CarSolar HeaterSolar LightsAPPLICATIONSSOLAR WATER HEATERWorking principle of solar water heater is below. Water from the cold supply is led to the cold store, then it passes into the preheat vessel, forming the warm store, where the cold water is heated by solar energy upto a certain temperature. From the warm store the water is transferred to hot storage where the hot water is further heated by boiler or electric heater.Hot water storage tankWarm water storage tankCold water storage tankMain water supplyHot water to utility pointsHeat from auxiliary heaterHeat from solar energySOLAR REFRIGERATION AND AIR CONDITIONINGAqua-ammonia Absorption System:It is useful even for residential requirements due to its wide range of operating conditions (up to 0 degree C) and non-requirements for cooling tower.The main limitation in commercializing the solar operated aqua-ammonia air conditioning unit is the requirement of generator temperatures in excess of 150 degree C which is beyond the supply limit of flat-plate collectors therefore the generator has to be completely redesigned so that the same can be made operational by the hot water at the temperatures around 100 degree C.Fig.: Schematic representation of aqua-ammonia absorption cooling system

Lithium Bromide Water Absorption System: It can provide evaporation temperature around 5 degree C, and operates in the pressure range of 4 to 0.8 KPa. In this system, water acts as a refrigerant and lithium bromide acts as an absorbent. In this cycle, water gets evaporated from the hot weak solution and finally gets absorbed in the cold strong solution. Cooling is produced during evaporation of water which takes place in the reabsorption process. The only problem in the lithium bromide-water system is the risk of crystallization of lithium bromide which may happen due to either low condenser temperature or high generation temperature.Fig.: Schematic representation of solar operated LiBr-H2O absorption cooling system

SOLAR THERMAL POWER SYSTEM Direct conversion of solar energy into electrical energy is practically not adopted for commercial purposes for large power demands due to high cost of cells.

Solar energy first converted into thermal energy then thermal energy into electric energy.

A solar thermal power system consists mainly of a solar energy collector field, some kind of fossil fuel combustor (auxiliary system), a fluid flow distribution system, some kind of suitable thermal energy storage device, a heat engine, electric generator, and a control system.Fig.: Simplified block diagram of a solar thermal power system

SOLAR WATER PUMPING The solar energy is directly converted into electricity using photovoltaic (solar) cells. This electricity is either stored in batteries or used directly in D. C. motors or converted into A. C. using inverter and then used in conventional water pumps.Fig.: Solar (Photovoltaic) Water Pumping

Fig.: The photovoltaic water pumping schemeSolar EnergySolar CellsCharge RegulatorBatteriesWater PumpA. C. MotorD. C.-A. C. InverterD. C. MotorWater PumpPROJECTS ON SOLAR ENERGY IN INDIA

SOLAR ENERGY POWER IN INDIA: FUTUREIn solar energy sector, many large projects have been proposed in India- Thar Desert has some of Indias best solar power projects, estimated to generate 700 to 2,100 GW. On March 1st, 2014, the then Chief Minister of Gujarat, Narendra Modi, inaugurated at Diken in Neemuch district of Madhya Pradesh, Indias biggest solar power plant. The Jawaharlal Nehru National Solar Mission (JNNSM) launched by the Centre is targeting 20,000 MW of solar energy power by 2022. Gujarats pioneering solar power policy aims at 1,000 MW of solar energy generation.About 66 MW is installed for various applications in the rural area, amounting to be used in solar lanterns, street lighting systems and solar water pumps, etc.SOLAR ENERGY PROS Solar panels give off no pollution. Solar energy produces electricity very quietly. Very efficient in large areas of the globe. It is affordable in the long run. The use of solar energy to produce electricity allows the user to become less dependent on the worlds fossil fuel supplies. We dont need a power or gas grid to get solar energy. A solar energy system can be installed anywhere. Solar panels can be easily placed in houses. Hence, it is quite inexpensive compared to other sources of energy.SOLAR ENERGY CONS The major con of solar energy is the initial cost of solar cells. Solar energy is only able to generate electricity during daylight hours. This means for around half of each day, solar panels are not producing energy for your home. The weather can affect the efficiency of solar cells. Pollution can be a con of solar energy, as pollution levels can affect a solar cells efficiency, this would be a major con for businesses or industry wishing to install solar panels in heavily polluted areas, such as cities. The land space required to install a solar plant with solar panel is quite large and that land space remains occupied for many years altogether and cannot be used for other purposes.REFERENCESH P Garg, J Prakash, SOLAR ENERGY: Fundamentals and Applications, Tata McGraw-Hill Publishing Company, New Delhi, 1997.Wikipedia, The Free Encyclopedia.http://en.wikipedia.org/wiki/Solar_energyhttp://en.wikipedia.org/wiki/Solar_power_in_India#Current_statusT.M. Razykov, C.S. Ferekides, D. Morel, E. Stefanakos, H.S. Ullal, H.M. Upadhyaya, Solar photovoltaic electricity: Current status and future prospects, 3 Jan. 2011, Solar Energy Research Institute, UKM, Bangi, Selangor, Malaysia.THE ENDTHANK YOU