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Our Energy. By Hana Bull && Jennii Derry. The energy we have chose.... is . WIND ENERGY. WHY ?!?!?. We chose Wind Energy because it is a renewable energy re-source. England doesn’t have the best weather conditions and we have a lot of rainy… and windy conditions… this is very helpful.
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Our Energy By Hana Bull && Jennii Derry
The energy we have chose.... is .... WIND ENERGY
WHY ?!?!? • We chose Wind Energy because it is a renewable energy re-source. • England doesn’t have the best weather conditions and we have a lot of rainy… and windy conditions… this is very helpful. • Wind && Rain are both re-newable sources making them both perfect choices.
Nerdy Bit ! • When the wind blows over the blades of a wind turbine, their aero-dynamic shape makes them turn. • When air passes over an aero-dynamic part, it travels faster over the top of the blade than it does below. This makes the air pressure above the blade lower than it is below. Due to the unequal pressures the blade experiences a lifting force. You can see this if you hold a thin sheet of paper to your lips and blow over the top of it. This will make the paper rise more than if you blow underneath it. The opposite force is drag, due to surface friction and turbulence. Wind turbine designers use these forces generated by the wind to make the rotor blades turn.
Last Nerdy Bit! ... • This rotational energy is transmitted either to an electrical generator or to a machine for mechanical work, such as a water pump. With electricity generating turbines, a gearbox is used to speed up the rotation, about 30 times. In mechanical turbines a shaft connects the turbine to the working machine. • Energy is extracted from the wind as it moves through the 'swept area' of the turbine's blades. On the down wind side of the turbine the wind moves more slowly, as some of its kinetic energy has been lost.
Emissions Reductions Every unit (kWh) of electricity produced by the wind displaces a unit of electricity which would have been produced by a power station burning fossil fuel. This is a fact used by many organisations including Government in their environmental calculations. Wind turbines produce electricity by using the natural power of the wind to drive a generator. The wind is a clean and sustainable fuel source, it does not create pollution and it will never run out. Wind energy technology is developing fast, turbines are becoming cheaper and more powerful, bringing the cost of renewably-generated electricity down. Europe is at the hub of this high-tech industry.
Disadvantages Some people say that wind turbines are ugly, but this could easily be resolved by designing new styles of wind turbines. If you have a small garden or live in a small town which is cramped all ready. You wont want a huge wind turbine on your roof or In your town. They need lots of space. They need wind and if you have a wind turbine in a country that hardly has any wind this will not be the ideal solution for you!
The Need For Clean Energy The Most Common methods of generating electricity burn fuel to provide the energy to drive a generator, usually by using the heat to provide steam to drive a turbine. These technologies may use fossil fuels, - coal, oil or gas - or nuclear fuel. Using fossil fuels creates pollution, such as oxides of sulphur and nitrogen which contribute to acid rain, and carbon dioxide which contributes to global climate change. Although these sources of power dominate the energy needs of European countries, wind energy is growing rapidly. Renewable energy sources currently provide nearly 5.4% of the European Union's primary energy needs and have the potential to provide much more.
How Wind Turbines Work Rotor diameters range up to 80 metres, smaller machines (around 30 meters) are typical in developing countries Wind turbines can have three, two or just one rotor blades. Most have three. Blades are made of fibreglass-reinforced polyester or wood-epoxy. The blades rotate at 10-30 revolutions per minute at constant speed, although an increasing number of machines operate at a variable speed. Power is controlled automatically as wind speed varies and machines are stopped at very high wind speeds to protect them from damage. Most have gearboxes although there are increasing numbers with direct drives. The yaw mechanism turns the turbine so that it faces the wind. Sensors are used to monitor wind direction and the tower head is turned to line up with the wind.
