Wind power

The Italian research about wind power

A PowerPoint presentation about the use of wind energy in Sannio

History of wind power

We have been harnessing the wind’s energy for hundreds of years. From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain. Today, the windmill’s modern equivalent- a wind turbine- can use the wind’s energy to generate electricity.
Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind. Turbines catch the wind’s energy with their propeller- like blades. Usually, two or three blades are mounted on a shaft to form a rotor.

Basic Aerodynamic Operating Principles of Wind Turbines

A blade acts much like an airplane wing. The wind passes over both surfaces of the airfoil shaped blade. It passes more rapidly over the longer (upper) side of the airfoil, creating a lower pressure area above the airfoil. The pressure differential between top and bottom surfaces results in a force, called aerodynamic lift. In an aircraft wing, this forces causes the airfoil to “rise”, lifting the aircraft off the ground. Since the blades of a wind turbine are constrained to move in a plane with the hub as its center, the lift force causes rotation about the hub.

As we have seen, when the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift.
The force of the lift is actually much stronger than the wind’s force against the front side of the blade, which is called drag.
The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity.

Nacelle

This is the steel and fibreglass casing that supports and covers the gearbox and generator. The nacelle can move through 360° and is turned into the wind using “yaw” motors that are controlled by the wind vane. The nacelle and equipment weigh 19 tonnes.

Gearbox

The main shaft, rotating at 28 rpm, is connected to the gearbox. The gearbox increases the speed of rotation to 1,500 rpm, and drives the generator.

Generator

The generator (3-phase, 690 volt) is driven by the high-speed shaft and also turns at 1,500 rpm, supplying electricity through a low voltage transformer to a high voltage transmission transformer and into Country Energy’s distribution grid.
If you have got a dynamo lamp on your bicycle, you already know a generator. The dinamo generates electricity for the lamp on your bicycle, when the wheel of the bicycle makes the wheel of the dinamo turn.

Weather instruments

These are attached to the back of the nacelle. A 3-cup anemometer spins to measure the wind speed and the wind vane records the wind direction. It is important to know how much wind there is because if the wind is too strong the wind turbine can break.

Mechanical brake

This is used to stop the blades rotating in gale force winds or for maintenance purposes. It is hydraulically operated using the same principles as found in a car’s disc brakes.

Rotor
All large wind turbines have three rotor blades fixed to the main shaft.Together these blades are called the rotor.

Blades
The turbine blades are made of fiberglass. The profile and shape of the blade is designed for maximum efficiency and minimum noise.

Hub
The hub is made of cast iron and connects turbine’s blades to the main shaft. When the wind blows, the blades and hub rotate at 28 revolutions per minute (rpm).The hub and blades together weigh 8.5 tons

The Italian research about wind power A PowerPoint presentation about the use of wind energy in Sannio
History of wind power We have been harnessing the wind’s energy for hundreds of years. From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain. Today, the windmill’s modern equivalent- a wind turbine- can use the wind’s energy to generate electricity. Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind. Turbines catch the wind’s energy with their propeller- like blades. Usually, two or three blades are mounted on a shaft to form a rotor.
Basic Aerodynamic Operating Principles of Wind Turbines A blade acts much like an airplane wing. The wind passes over both surfaces of the airfoil shaped blade. It passes more rapidly over the longer (upper) side of the airfoil, creating a lower pressure area above the airfoil. The pressure differential between top and bottom surfaces results in a force, called aerodynamic lift. In an aircraft wing, this forces causes the airfoil to “rise”, lifting the aircraft off the ground. Since the blades of a wind turbine are constrained to move in a plane with the hub as its center, the lift force causes rotation about the hub.
As we have seen, when the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift. The force of the lift is actually much stronger than the wind’s force against the front side of the blade, which is called drag. The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity.
Nacelle This is the steel and fibreglass casing that supports and covers the gearbox and generator. The nacelle can move through 360° and is turned into the wind using “yaw” motors that are controlled by the wind vane. The nacelle and equipment weigh 19 tonnes.
Gearbox The main shaft, rotating at 28 rpm, is connected to the gearbox. The gearbox increases the speed of rotation to 1,500 rpm, and drives the generator.
Generator The generator (3-phase, 690 volt) is driven by the high-speed shaft and also turns at 1,500 rpm, supplying electricity through a low voltage transformer to a high voltage transmission transformer and into Country Energy’s distribution grid. If you have got a dynamo lamp on your bicycle, you already know a generator. The dinamo generates electricity for the lamp on your bicycle, when the wheel of the bicycle makes the wheel of the dinamo turn.
Weather instruments These are attached to the back of the nacelle. A 3-cup anemometer spins to measure the wind speed and the wind vane records the wind direction. It is important to know how much wind there is because if the wind is too strong the wind turbine can break.
Mechanical brake This is used to stop the blades rotating in gale force winds or for maintenance purposes. It is hydraulically operated using the same principles as found in a car’s disc brakes.
Rotor All large wind turbines have three rotor blades fixed to the main shaft.Together these blades are called the rotor. Blades The turbine blades are made of fiberglass. The profile and shape of the blade is designed for maximum efficiency and minimum noise. Hub The hub is made of cast iron and connects turbine’s blades to the main shaft. When the wind blows, the blades and hub rotate at 28 revolutions per minute (rpm).The hub and blades together weigh 8.5 tons