WIND POWER PLANT Wind Power Plant

WIND POWER PLANT Introduction to renewable sources. Need of wind power plant Site selection Operating principle Working & power generation Merits and demerits Present scenario & future

Generalities on wind The Earth continuously releases into the atmosphere the heat received by the sun, but unevenly. In the areas where less heat is released(cool air zones) the pressure of atmospheric gases increases, whereas where more heat is released, air warms up and gas pressure decreases.

How Does Wind Blow The sun heats the earth’s Surface unevenly. As heat is transferred to the air, we get regions of warm and cool air which can turn into regions of low and high pressure. This difference in pressure makes a force that causes the wind to blow.

Principle Of Energy Conversion : Windmills or turbines works on the principle of converting kinetic energy of the wind in to mechanical energy. Power available from wind mill- P= ½d A V³ Where- d :- air density = 1.225 Kg. / m³ at sea level.(changes by 10-15% due to temperature and pressure variations) A :- area swept by windmill rotor = dD² sq-m. (D – diameter ) V – wind speed m/sec.

SITE SELECTION Most important decision throughout your installation. Vital part in the performance and efficiency of a wind turbine. High, exposed sites. Not suitable sites in highly populated residential areas. Avoid roof mounted turbines. Power transmission loss Distance between the turbine and the nearest obstacle Connection with national power grid

WORKING OF WIND POWER PLANT: Wind turbines harness the wind's energy to generate electricity. Here, in short, is how they do it: Wind makes BLADES turn. Blades turn a shaft . Gearbox connected to shaft increases ROTATIONAL speed. Direct drive, Gearless technology CONVERSION : Mechanical energy Electrical energy. Power inverter Transformer : output voltage of inverter / 11 KV – 33KV. Local distribution / national greed.

PARTS OF WIND TURBINE : 1. Hub controller 11. Blade Bearing 2. Pitch cylinder 12. Blade 3. Main shaft 13. Rotor lock system 4. Oil cooler 14. Hydraulic Unit 5. Gear Box 15. Hydraulic shrink disk 6. VMP top-controller 16. Yaw ring 7. Parking break 17. Machine foundation 8. Service crane 18. Yaw gear 9. Transformer 19. Generator 10. Blade Hub 20. Generator Cooler

PARTS OF WIND TURBINE :

Rotor: The rotor consists of the hub, three blades and a pitch regulation system, all of which are located upwind of the tower. The design speed of the rotor is 16 rpm. Transmission system: The mechanical power generated by the rotor blades is transmitted to the generator by the transmission system. This consists of a gearbox and a braking system plus the auxiliary lubricating and cooling systems. The gearbox is needed to increase the rotor’s speed (16 rpm) to the 1800-rpm speed of the generator. The braking system is designed to lock the rotor when shut down.

Generator: The generator converts the mechanical energy to electrical energy in an asynchronous (induction) generator. Yaw and control systems: The yaw system turns the nacelle into the actual wind direction using a rotary actuator and a gear mechanism at the top of the tower. A fully automatic microprocessor-based control and monitoring system is a part of the wind turbine. The control system is designed for remote operation from the shore-based operations center via a fiber optic communications system.

Types of Wind Turbines

1. Horizontal Axis Wind Turbines (HAWT) A HAWT has a similar design to a windmill It has blades that look like a propeller that spin non the horizontal axis.

HAWT Advantages: The tall tower base allows access to stronger wind in sites with wind shear. High efficiency, since the blades always move perpendicularly to the wind, receiving power through the whole rotation. Does not need reciprocating actions, requiring airfoil surfaces to backtrack against the wind for part of the cycle.

HAWT Disadvantages: Required Massive tower construction Obtrusively visible across large areas Downwind variants suffer from fatigue and structural failure. Require an additional yaw control mechanism Require a braking device

2. Vertical axis [VAWTs] Have the main rotor shaft arranged vertically.   By such arrangement is that the wind turbine does not need to be pointed into the wind. This is an advantage on sites where the wind direction is highly variable or has turbulent winds.

VAWT Advantages: No yaw mechanisms is needed. Can be located nearer the ground Lower wind startup speeds May be built at locations where taller structures are prohibited

VAWT disadvantages average decreased efficiency from a common HAWT, mainly because of the additional drag. Having rotors located close to the ground

ADVANTAGES AND DISADVANTAGES OF WIND POWER PLANT ADANTAGES: Energy For Free Of Cost. Produces Electricity Throughout The Day. Pollution Free And Clean. Vast Wind Energy Is Available. (10 Million Mw) Can Supply The Power To Remote Areas. Economically Competitive. Mechanical Power For Grading, Pumping Etc. ; Using Wind Energy. Wind Energy Domestic, Renewable Source Of Energy . Up To 95 % Land Of Wind Farms Can Be Used For Ranching, Farming And Forestry.

DISADVANTAGES: Low energy density. Irregular , unsteady wind energy Variable speed. Variable wind direction. Higher capital cost. Can be located only in vast open areas . Far location from load centers. Complex designs.

Present Scenario: Started development in 1990s.  India has the fifth largest installed wind power capacity in the world As of 31 Jan 2013 the installed capacity of wind power in India was 19779.15 mw State-level wind power: Tamilnadu - 7158 mw Generates 40% of India's wind power. Major districts - coimbatore, kanyakumari ,thirunelveli, and tiruppur. Gujarat -3093 mw Total installed capacity in Gujarat stood at 3093 mw. Maharashtra -2976 mw Third in terms of power generation using wind energy. Rajasthan -2355 mw 2356 MW as per TOI, dated 31.3.2012.

WIND POWER PLANT’S STATUS ALL OVER THE WORLD

Future: The Ministry of New and Renewable Energy (MNRE) has fixed a target of 10,500 MW between 2007–12, but an additional generation capacity of only about 6,000 MW might be available for commercial use by 2012. The Ministry of New and Renewable Energy (MNRE) has announced a revised estimation of the potential wind resource in India from 49,130 MW assessed at 50m Hub heights to 102,788 MW assessed at 80 Hub height. The wind resource at higher Hub heights that are now prevailing is possibly even more .

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