Wind Energy As a Renewable Source

Wind energy is obtained from the wind, which can be converted into many other useful forms of energy. Wind is caused by the difference in air pressure from one place to another. The temperature of a place varies from another which causes warmer air to rise and cold air is replaced in that place. The wind blows from a higher pressure area to the lower pressure. The speed of wind depends on several factors such as temperature, air pressure, geographical location, rotation of the earth, etc. Wind energy has been harnessed by mankind for different purposes such as sailing a ship, windmills for grinding corn, pumping water, blowing off chaff from the grains etc.

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Wind Turbines

Wind energy can also be harnessed and utilized for generating electricity. It is used to propel the blades of the wind turbines. When the wind blows it turns the blades of the turbine, the mechanical energy of the rotating blade is converted into electrical energy in the turbines. Wind turbines are suitable where the force of the wind is strong and steady, producing more electricity. Places such as offshore, coastal areas, hill tops, and mountainous gaps etc. has strong wind currents. The wind turbines are fixed on long wind turbine posts where the turbine and the blades are fixed. The height of the tower is taller so that the blades are high enough to catch the wind where it is stronger.

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The propellers or blades of the wind turbines are made large enough so that they can harness even the faintest of the air currents. The blades are angled to drive the turbine and also to provide rotation at all wind speeds, which are measured before installation. The propeller is also designed to turn to the direction of the wind so that it can move with the wind coming from any direction. The electricity generator of the turbine is mounted behind the turbine where the electricity is produced.  Electricity is transmitted through long electric transmission lines to the central grid connecting the households. Large scale wind towers together, known as wind farms, provide electricity to many households while small and individual wind turbines provide electricity to individual houses or neighborhoods. More wind turbines are needed to cover the electricity deficit in many towns and cities. The land beneath the wind turbines can be used for other purposes as well.

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Advantages

Wind energy is non polluting and does not cause the production of greenhouse gasses.

Wind energy is a renewable source of energy that is constantly renewed and never run out.

The land area that is used for wind farm can still be used for other purposes such as agriculture, farming, grazing etc.

Wind mills can be built offshore and on rocky coasts, where the force of the wind is greater and therefore reliable source of electricity and there is no interference on land.

Drawbacks

Wind energy is intermittent because the wind is not constant at all times and not predictable.

Consistent wind is needed for continuous and sustained power generation.

Big wind farms will have a negative impact on the scenic beauty of the place.

Wind mills may cause harm to migratory birds that pass through very large wind farms.

It can cause television interference when you live nearby a wind turbine.

Wind turbines can be noisy and can irritate you when you sleep.

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Biomass Energy As a Renewable Source

Biomass Energy

Biomass  energy comes from the biological matter and residues of plants or animals either living or recently living organisms, which can be used for energy generation. The plants store  energy from the sun through the process of photosynthesis. When the  plants or plant products are burned, it releases the stored energy they  contain. Biomass energy functions as a stored energy like a battery where the energy is stored during the growth of the plant and releases it when it is burnt. The plant and plants products such as wood,  crops, leaves, bark, garbage etc. can be used as a fuel for heating, cooking, electricity production etc. The biomass energy is sustainable  when the production of biomass is equal to the amount of biomass that is  utilized as fuel.

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A different variant of biomass energy is the biofuel. The biofuels are  derived from the biomass which is bioconverted into, solid biomass, liquid biofuels, and biogases. The solid biofuels include wood chips, yard clippings, solid waste materials and  residues after human consumption and plantation crops such as  sugarcane. Wood is burned to produce fire and heat which is used for cooking as well as heating rooms at fireplace etc. Solid wastes are used to provide heat or generate electricity in a power station.

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Bioconversion of the biomass produces liquid biofuels which include bioethanol and oils such as  biodiesel. Bioethanol is an alcohol produced by fermentation of sugar, starch, and cellulose component of plants and plant materials. Sugarcane and corn are commonly used for producing bioethanol. Ethanol  is used as a fuel for driving vehicles. Biodiesel is made  from left over vegetable oils, animal fats, etc. It can be used as a fuel for  vehicle as a pure form and also used as an additive in diesel powered  vehicles. Gaseous biofuels include biogas, landfill gas, synthetic gas  etc. Biogas, landfill gas, or methane gas is produced as a result of the the biomass decay such as rotting garbage, agricultural waste, etc. Biogas is used as a fuel for cooking and heating purposes.

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Advantages

Biomass energy is a form of renewable energy and so can be used in place of fossil fuels.

It can be used as and when needed for burning, cooking, or as fuel in vehicles.

It is cheaply available in the environment and can be produced by growing biomass plants and using or processing it for energy.

It is especially suited for remote villages and households where there is excess biomass collection.

When the usage of biomass is balanced with the growth of new biomass plants and crops the effect on global warming is reduced.

Drawbacks

Biomass produces carbon dioxide as a byproduct after burning that contributes to pollution.

It can contribute a little to global warming by emission of greenhouse gases such as carbon dioxide.

Collection of biomass waste is sometimes difficult and the raw materials are not available year round.

 

Solar Energy As a Renewable Source

Solar Energy
Solar energy is the energy available as the solar radiation from the sun. Sun is the source of almost all the energy that is available on earth. It is the single and most viable alternative source of energy. It is about 150 million kilometers away from the Earth. Sun shines brightly and huge amount of radiation energy reaches the earth. The amount of Sun’s energy reaching the earth is enough to meet all the human energy need; the limitation is to harness them. Most of the energy utilized by the green plants and fossil fuels derive their energy from the Sun. The energy from the water, wind, and tides are all the result of the interaction of sun's energy with the Earth's atmosphere. It is a non depleted source of energy that man can depend on for many years to come. Solar energy is used by harnessing the Sun's  radiation to be converted into electricity, solar thermal panels to heat  water or air for heating rooms, solar thermal generator etc. The Sun’s energy has been used for drying clothes and foods.

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Solar energy technology can be classified into passive solar devices and active solar devices depending upon the capture, conversion, and distribution of solar energy. Solar energy can be utilized in various ways such as using solar panels to generate electricity, solar thermal solution for cooking and heating rooms, day lighting, desalination of salt water for drinking water, used in thermal generator for production of electricity etc.

Uses of Solar Energy

Solar home heating is where solar energy or heat from the Sun can be used to heat the home and interiors. The Sun’s heat is directed to solar collector panels that are filled with fluid such as water or air. These panels are mounted on a Sun-facing roof or wall that admits Sun light. Water or air is circulated through pipes along these panels, which get heated by the exposure to Sun light. This heated fluid or air is then circulated around the house through pipes for warming purposes. This helps the centralized heating system which can help save the fuel costs.

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Solar furnace is used to cook food and drinks. It consists of a huge array of mirrors that concentrates the Sun’s energy into a small area, which produces very high temperatures. Solar furnace is used as a solar cooker for cooking foods and drinks especially when the whether is hot and warm and in warm climates.

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Solar panels or photovoltaic panels are used to convert solar energy into electricity. These are used mostly for powering satellites in space. There are many electronic devices that work with the help of solar panels such as calculators, video games, etc. It can also supply power to appliances such as electric bulbs, fans, and other electrical devices. Solar power panels can supply energy to the entire house by storing the electrical energy in a battery and then powering an inverter to produce the AC line voltage. Good storage batteries and sufficient solar panels can help supply several hours of electricity to the house, mostly at night when the sun is not shining. The home solar system can almost entirely supply the home energy need and can save electricity bills. Solar panels can also power devices such as mobiles, laptops, notebooks etc. It can also charge rechargeable batteries used in small electronic devices.

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Solar power station produces electric power by a solar thermal generator. Here many solar reflectors or mirrors are used to concentrate the rays of the Sun to a central power tower. The mirrors are mounted in such a way that it always faces the Sun at all times of the day. Its position is maintained using a motorized rotator that turns, so that the Sun's energy is reflected straight to the tower. The mirrors reflect the Sun’s energy to the central tower where enough heat is generated to heat the oil in the power generator around 3000 degrees Celsius. The heat in the oil is used to generate steam in a steam chamber that drives the generator which produces electric power.

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Advantages:

Solar energy is a renewable source of energy that can be utilized without it getting exhausted.

Solar  energy is non polluting and is not a source of pollution of either air,  water and there are no byproducts formed as a result of solar  radiation.

It  can help to prevent the excessive burning of fossil fuels and the  resultant pollution in the form of air pollution, water pollution, smog,  acid rain etc.

Solar  energy can be utilized in various means such as by solar panels, solar  water heaters and cooking utilities, solar furnaces, solar thermal power  generation etc.

Solar energy is a very efficient form of energy which can be effectively utilized for human needs.

The  durability of solar panels used for electricity production is 25 years  and more and the cost and efficiency of the panels are coming  drastically down.

Drawbacks:

Solar energy is not produced with the absence of the sun during night and on cloudy skies or rainy days.

Solar energy production infrastructure can cost somewhat high at the beginning but later pays off.

Important Renewable Sources of Energy

The energy that comes from non renewable sources such as burning of fossil fuels gets depleted over a period of time and then eventually will run out. Fossil fuels such as coal and petroleum and the important fuels that are used today and their reserves are getting rapidly depleted and very high prices are being payed for procuring them. The burning of fossil fuels also causes massive amount of pollution and exhaustion of gases such as carbon dioxide, carbon monoxide, and sulfur dioxide that are harmful for health and also will result in the formation of greenhouse effect and global warming.

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Meanwhile renewable energy is the energy that is obtained from non depleted natural resources such as sunlight, wind, rain, tides, geothermal etc. These sources are naturally replenished and does not get depleted very soon. Around 16% of the global energy output comes from the use of renewable energy. From that, around 10% energy is obtained from biomass energy and 3.4% from hydroelectric energy. The rest comes from non renewable sources such as fossil fuels including petroleum, natural gas, coal, lignite, peat, wood, and nuclear materials, etc. Renewable energy account for the 19% of electricity that is generated worldwide.

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​Renewable energy is derived from natural processes that are replenished constantly. It derives energy directly from the sun or the energy generated deep within the earth's crust. The important areas where renewable sources of energy are mostly used are, for electricity generation, hot water/space heating, and transport fuels. The deteriorating climate, global warming, high oil prices, diminishing fossil fuel reserves, increasing government support and subsidies, are the driving factors that push the renewable energy industry to surge ahead. It is being projected by the International Energy Agency that solar power generators may produce most of the world's energy within 50 years.

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The increasing use of renewable energy sources will drastically reduce the emissions of greenhouse gases and thus limiting global warming. There is increasing support for alternative and renewable sources of energy that requires one to use more renewable energy and providing tax incentives to encourage the development of these technologies. There is considerable optimism that the investments in the renewable energy will pay off in the long term.

​The important renewable energy sources include:

Solar.energy

Wind energy

Hydroelectric energy

​Tidal energy

Geothermal energy

Biomass energy

Hydrogen fuel energy

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