Essay on windmill energy

Short Essay on Wind Energy (260 Words)

Wind is air in motion. It is caused by the uneven heating of the earth’s surface by the sun. Since the earth’s surface is made of different types of land and water, it absorbs the sun’s heat at different rates.

During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating winds. At night, the winds are reversed because the air cools more rapidly over land than over water.

In the same way, the large atmospheric winds that circle the earth are created because the land near the earth’s equator is heated more by the sun than the land near the North and South Poles.

Today, wind energy is mainly used to generate electricity. Wind is called a renewable energy source because the wind will blow as long as the sunshines.

Working of Wind Machines:

Like old fashioned windmills, today’s wind machines use blades to collect the wind’s kinetic energy. Windmills work because they slow down the speed of the wind. The wind flows over the airfoil shaped blades causing lift, like the effect on airplane wings, causing them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity.

With the new wind machines, there is still the problem of what to do when the wind isn’t blowing. At those times, other types of power plants must be used to make electricity.

Short essay on Wind Energy

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Wind energy is an important non-conventional source of energy. There is a simple relation between wind, velocity and power. If a wind with a velocity of 10 km per hour gives one horse power, a 20 kmph wind will produce 8 hp.

Winds with speed from 12 to 20 kmph capable of moving leaves and small twigs are available at many places for several months of the year. These can be tamed and tapped successfully for power generation.

Source of Wind Energy

The energy possessed by wind is because of its high speed. The source of wind power is inherent in solar energy. Our earth gets only 2,000 millionth part of the total solar energy out of which about 20 per cent is converted into kinetic wind energy.

Areas Suitable for Developing Wind Machines

Areas which are quite windy and average wind intensity of 3 KW/m 2 /day is prevalent at a number of places in peninsular India as also along coastlines in Gujarat, Western Ghats and parts of Central India.

In our country along the Western Ghats the area in the east of Palghat Gap (Coimbatore District) is most favourable for wind power generation.

The development of wind machines is especially relevant in arid and semi-arid zones of Rajasthan.

These areas have high velocity winds throughout the year. In some ridges and slopes of hills swift wind blow where wind energy can be profitably harnessed at Palghat and Tuting in Arunachal Pradesh, the average wind speed recorded was 9.5 kmph while in many areas of Nagaland, Mizoram, Meghalaya and Manipur, it varies from 3 to 6 kmph. In these areas, low speed windmill can operate.

Advantages

1. Wind power is abundantly available, free of cost and is pollution free.

2. The wind is more reliable high above the ground level in many mountainous regions

3. For regions remote from coal or oil fields and with ample wind available, wind power is a blessing.

4. The endless surge of wind is a potential power source and may well provide an answer to the problem of growing energy demands in the future.

Applications

1. In India, the exercise to harness wind energy includes wind pump, wind battery charges, wind electricity generators and grid connected wind farms.

2. The Kharif crop, normally between June and October, is largely rainfed. Wind mills could however be used to pump water for rural irrigation in the Rabi season.

3. Wind energy may be converted into mechanical and electrical energy. About 20,000 MW of electricity may be generated in India from wind.

Limitations

1. Wind is erratic and unreliable. It requires special conditions for its economic exploitation.

2. Winds have a high seasonal bias. They are much stronger during the monsoon than during the rest of the year. The possibilities of predicting wingspread at a particular time of the year are rather poor.

3. It is not available in all the places to do various types of work.

4. Location of wind farms on migratory routes could spell hazard to birds and disaster for some aviation populations.

5. Their appearance on the landscape and their continual whirring and whistling can be irritating.

Wind Energy: Essay on Wind Energy Available in India

Essay on Wind Energy Available in India!

The unequal heating of the Earth’s surface by the sun is responsible for the circulation of air in the atmosphere. Air immediately above a warm area ex­pands. Being lower in density it is forced upwards by the cooler denser air flow­ing in the surroundings, resulting in wind.

As wind is caused by the unequal heating of the air it can be said to be an indirect form of solar energy. Wind energy is a renewable source of non polluting energy. It has tremendous potential which, if harnessed, can easily satisfy the energy demands of a coun­try.

Estimates reveal that two percent of the total solar energy falling on earth is converted to kinetic energy in the atmosphere. 30 percent of this kinetic energy occurs in the lowest 1000 m of elevation i. e. wind in this lowest kilometer has maximum kinetic energy which can be converted into mechanical energy which in turn can be utilized to generate electricity or to perform some other useful work. Since the energy possessed by wind is by virtue of its motion, so the de­vice used to extract its energy should be capable of slowing down the wind.

Wind energy conversion devices like wind turbines are used for converting wind energy into mechanical energy. Wind turbines consist basically of a few sails, vanes or blades radiating from a central axis. When wind blows against the blades or vanes, they rotate about the axis. This rotational motion is utilised to perform some useful work. By connecting the wind turbine to an electric generator wind energy can be con­verted into electric energy.

In India, winds are relatively low (5 km/hr to 15/20 km/hr) and vary appreci­ably with season. This makes the exploitation of wind energy an expensive project.

However, it is useful in those areas with more or less steady winds and remote areas which are far removed from central power grids where electric power is not available due to high cost of generation and distribution to small dispersed users. In rural areas, windmills have been used since ages for grinding grain and pump­ing water for drinking, washing and irrigation.

Research in the exploitation of wind energy is being carried out by many insti­tutes namely:

(a) Marine Chemicals Research Institute, Bhavnagar.

(b) National Aeronautical Laboratory (NAL), Bangalore.

(c) Central Arid Zone Research Institute (CAZRI), Jodhpur.

(d) Madurai Wind Mill, Madurai.

In 1986, the first wind farm project was installed in Mandi in Gujarat. Such windmills successfully fulfill the local power requirements besides selling power to the state. Wind energy is available in dilute form and is fluctuating in nature necessitating storage capacity and an alternate source of energy to fall back on in case of non availability of winds.

The present day wind energy systems are not very reliable in practice besides being a source of immense noise pollution. More developmental work is needed in order to fully harness the tremendous potential of this important natural non-polluting renewable energy resource.