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JOIN HANDS TO SAVE OUR EARTH . Student teacher- Shaikh Rafat Deshmukh Sulakshana Guide- Prof. Desale S.Y. ENERGY. W hat is energy? Energy is what makes things go. W here do we humans get our energy from to move? Food. Renewable Energy sources:
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ENERGY • What is energy? • Energy is what makes things go. • Where do we humans get our energy from to move? • Food
Renewable Energy sources: • Energy sources that can be produce again and again are called renewable energy sources. • Examples: wind energy, tidal energy, solar energy, nuclear energy etc. Non renewable energy sources: • Energy sources that cant be produce again and again are called non renewable energy sources. • Examples : petrol, diesel , coal etc.
Solar Energy : • As oil prices spike, people are looking for alternative energy sources to save money. Here are solar energy advantages and disadvantages, with advantages definitely winning out. • Solar energy can be defined rather simply as the conversion of sunlight into usable energy. Currently, solar energy is used to provide electricity to homes, businesses, schools, universities and space vehicles used by NASA. As traditional energy prices rise, solar energy use is growing at a rate of 25 percent a year. .
Need Of Solar Energy: What is meant by solar energy? Why there is a need of solar energy? How we can use this energy?
Solar Energy Advantages • The power source of the sun is absolutely free. • The production of solar energy produces no pollution. • The technological advancements in solar energy systems have made them extremely cost effective. • Most systems do not require any maintenance during their lifespan, which means you never have to put money into them. • Most systems have a life span of 30 to 40 years. • Most systems carry a full warranty for 20 to 30 years or more. • Unlike traditional monstrous panel systems, many modern systems are sleeker such as Uni-Solar rolls that lay directly on the roof like regular roofing materials. • In 35 states, solar energy can be fed back to the utilities to eliminate the need for a storage system as well as eliminating or dramatically reducing your electric bills. • Solar energy systems are now designed for particular needs. For instance, you can convert your outdoor lighting to solar. The solar cells are directly on the lights and can’t be seen by anyone. At the same time, you eliminate all costs associated with running your outdoor lighting
Solar Energy Disadvantages: • The primary disadvantage to solar energy is the upfront cost. Once installed, you can expect next to nothing on the system during the 40-year life span. • The installation, however, can be price. • Outdoor solar lighting will cost you no more than normal lighting, but large solar energy systems for your entire home can run from a minimum of $15,000 to a more likely figure of $25,000 to $35,000. • While this isn’t cheap, state and federal governments have created significant ways to offset this cost. The federal government wants as many people to covert to solar as possible. • The goal is to have a million solar roofs by the year 2010 to ease the stress on electrical grids across the nation. To promote this, the federal government offers the following incentives: Up to a $2,000 tax credit in year of installation. Importantly, a tax credit is applied to the actual amount of tax you owe, not a deduction from your gross. If you prepare your taxes and find you owe $10,000, this tax credit will reduce the amount to $8,000. • The federal government offers incentives in home loans. If you go solar, lenders will give you breaks under the Energy Efficient Mortgage or Energy Improvement Mortgage programs. • The specific savings depend on the details of your home. State governments are also interested in promoting solar energy use. • To promote solar, 35 st • ates allow you to sell excess solar energy to utilities. Known as net metering, your solar system is tied into your utilities. During the day, the system feeds power into the grid and you can watch your meter run backwards! Net metering can effectively eliminate your utility bills for the life of the solar energy system. Think about that. No utility bills for 30 or 40 years!
Application of solar energy: Energy from the Sun is virtually limitless and provides the basis of life on Earth. When that energy is converted into something useful, it becomes solar power. Plants also transform sunlight into food energy through photosynthesis. Modern technology transforms solar energy into electrical power (electricity) with the use of photovoltaics PV). It converts solar energy into electricity by “exciting” the electrons of an atom into a higher state of nuclear orbit. The most efficient photodiodes (produces electric current when light is shone on it) for photovoltaics are those made from silicon-derived materials. Solar cells produce direct current electricity (DC) and were first used to power spacecrafts on their long journey or power orbiting satellites. More practical uses of this DC power nowadays include telecommunications cell sites, the cathodic protection of oil pipelines (from rust), roadside emergency telephones, and remote sensing. Its other uses are for remote fixed devices like temporary street signs or permanent traffic lights, or for portable devices such as calculators, computer laptops and wristwatches.
Solar power is energy from the sun and without its presence all life on earth would end. Solar energy has been looked upon as a serious source of energy for many years because of the vast amounts of energy that are made freely available, if harnessed by modern technology.A simple example of the power of the sun can be seen by using a magnifying glass to focus the suns rays on a piece of paper. Before long the paper ignites into flames. This is one way of using the suns energy, but flames are dangerous and difficult to control. A much safer and practical way of harnessing the suns energy is to use the suns power to heat up water.
Solar Thermal Electricity • Like solar cells, solar thermal systems, also called concentrated • solar power (CSP), use solar energy to produce electricity, but in a • different way. Most solar thermal systems use a solar collector with • a mirrored surface to focus sunlight onto a receiver that heats a • liquid. The super-heated liquid is used to make steam to produce • electricity in the same way that coal plants do. There are CSP plants • in California, Arizona, Nevada, and Florida. • Solar energy has great potential for the future. Solar energy is free, • and its supplies are unlimited. It does not pollute or otherwise • damage the environment. It cannot be controlled by any one nation • or industry. If we can improve the technology to harness the sun’s • enormous power, we may never face energy shortages again.
Photovoltaic Electricity Photovoltaic comes from the words photo, meaning light, and volt, a measurement of electricity. Sometimes photovoltaic cells are called PV cells or solar cells for short. You are probably familiar with photovoltaic cells. Solar-powered toys, calculators, and roadside telephone call boxes all use solar cells to convert sunlight into electricity. Solar cells are made up of silicon, the same substance that makes up sand. Silicon is the second most common substance on Earth. Solar cells can supply energy to anything that is powered by batteries or electrical power.
Solar Water Heating: • Solar energy can be used to heat water. Heating water for bathing, • dishwashing, and clothes washing is the second largest home • energy cost. Installing a solar water heater can reduce your water • heating bill 50 to 80 percent. • A solar water heater works a lot like solar space heating. In our • hemisphere, a solar collector is mounted on the south side of a roof • where it can capture sunlight. The sunlight heats water in a tank. • The hot water is piped to faucets throughout a house, just as it • would be with an ordinary water heater.
Electricity is produced when sunlight strikes the solar cell, causing the electrons to move around. The action of the electrons starts an electric current. The conversion of sunlight into electricity takes place silently and instantly. There are no mechanical parts to wear out. You won’t see many photovoltaic power plants today. Compared to other ways of making electricity, photovoltaic systems are expensive. In 2009, the DeSoto Next Generation Solar Energy Center in Florida opened. It is the largest photovoltaic plant in the country, generating 25 megawatts of electricity—enough to power 3,000 homes. It costs 10 to 20 cents a kilowatt-hour to produce electricity from solar cells. Most people pay their electric companies about 12 cents a kilowatt-hour for the electricity they use, and large industrial consumers pay less. Today, solar systems are mainly used to generate electricity in remote areas that are a long way from electric power lines.