Category Wind Energy

 

Over 50 countries use wind power to generate electricity. Around 72 percent of the world’s wind power is produced in Europe. Roughly 18 percent of the world’s wind power is produced in the USA. The use of wind power is increasing.

 

 

 

 

 

Many countries are now building giant wind farms to make electricity.

Germany and Spain are by far the world leaders in wind power production, but Denmark is the country that most relies on wind power. In 2004, wind power provided 19 percent of Denmark’s electricity. India and China are rapidly developing wind farms.

 

 

 

 

 

Wind power is growing very quickly across the world.

The use of wind power more than doubled between 2000 and 2004. It is one of the fastest growing types of energy, but it only produced less than one percent of the world’s electricity in 2002. The wind power industry plans to produce 12 percent of the world’s electricity by 2020.

 

Wind farms can be built offshore (out at sea). There is more wind energy at sea than there is on land. The electricity the farms produce is sent back to the land along underwater cables.

 

 

 

 

 

 

These homes use electricity generated by offshore wind power.

One of the most reliable places for wind is at sea. There are few obstacles at sea so the wind is smoother and less turbulent than on land. The first offshore wind farm in the USA could begin generating electricity in 2009. It is called the Cape Wind Project. If it is built, it will be located in Nantucket Sound off Cape Cod in Massachusetts.

 

 

 

 

Offshore wind farms are built using special equipment.

Calm weather is needed to build offshore wind farms. Only shallow coastal waters are suitable for offshore wind farms. In the future, floating and deeper-water wind farms may become possible.

1. Radar is used to help decide where to position the steel piles.
2. The steel piles are driven into the sea bed to support the turbine. The piles are coated with specialized resins and paint to stop them rusting, and painted brightly so that ships can easily see them.
3. The nacelle and rotor blades are placed on top of the steel piles.
4. The turbine is linked by underwater cables to an offshore transformer.

Divers are used to install the cables. A cable carries the electricity from the transformer back to shore.

 

 

A wind turbine needs a reliable supply of wind to generate electricity. The best land-based places for a wind farm are on coasts and areas of high ground.

 

 

 

 

 

 

Wind farms are built in windy places, such as on top of a hill.

More than half of the wind energy hitting a modern turbine can be converted into electricity, but only if the turbine is in the right location. The best locations are those with a regular wind and no obstacles to block the wind from reaching the rotor blades. This is why wind turbines are located on hills, cliffs or in a location where the wind is not blocked by any buildings.

 

 

 

 

The wind vane on top of the nacelle measures the direction of the wind.

To generate as much power as possible, a wind turbine must face into the wind. The wind vane sends signals to a yaw mechanism. The yaw mechanism uses a system of cogs to turn the nacelle and rotor blades into the wind.

 

 

 

 

 

 

An anemometer measures the speed of the wind.

The speed of the wind is very important for wind farms. If the wind is too slow, then the turbines will not work. If it is too fast, then they will shut down to avoid being damaged. Most turbines work in wind speeds of between 18 and 90 km/hour. An anemometer measures the wind speed and can automatically turn the turbine on or off as required.

Continue reading “Where to locate a wind farm?”

 

 

The blades of a modern wind turbine can be over 40 metres long and stand on a tower 80 metres high. In good winds, they can generate enough electricity to supply around 900 typical European homes.

 

 

 

 

 

 

The blades are attached to the nacelle. Inside the nacelle is the generator.

Modern wind turbines are very different from the early windmills. They are now made out of modern materials and controlled by electronics and computers. The main parts of a turbine are the tower, the nacelle and the rotor blades. The rotor blades are connected to the front of the nacelle and the whole lot sits on top of a tower.

 

 

 

 

 

Rotor blades are made to be lightweight but strong.

Most wind turbines have three rotor blades. The rotor blades have an aerodynamic shape (like an aeroplane wing) that helps them to catch as much wind energy as possible. Modern blades are made from materials such as carbon fibre, glass fibre and polyester. These materials allow the blade to bend a little in the wind without breaking.

 

 

 

 

 

 

 

Steel tubes are bolted together to make a wind tower taller than four houses!

The tower of a wind turbine is normally a steel tube that is bolted to a concrete base. The tube is made in sections and transported to the tower site on large Lorries. Cranes lift the sections into place and they are bolted together to form the tower.

 

 

Wind is created when energy from the Sun heats up the air around you. Of all the Sun’s energy that reaches the Earth, around one or two percent is changed into wind energy. This is an enormous amount of energy. For us to use it, it must be captured and turned into power.

 

 

 

 

The Sun creates wind energy that turns rotor blades.

Wind power uses the energy of the wind to turn rotor blades. The rotor blades are connected to a generator that produces electricity. The electricity is carried along wires to our homes and schools and to shops and offices.

 

 

 

Continue reading “How does wind power work?”

 

 

 

Wind energy plays an important part in the natural world. Seeds are carried by the wind to land where they grow into new plants. Birds use wind energy to help them travel over long distances. Wind energy also causes damage. It blows over trees, and brings huge waves and storms.

 

 

 

 

 

 

These geese are pushed along by strong winds called tail winds.

Some birds use the energy of the wind. It helps them travel long distances when they migrate from one country to another. Birds find strong winds that push them along. This saves them having to beat their wings as often. These winds are called tail winds. Aircraft also use tail winds to push them along.

 

 

 

 

The kite is lifted by the wind’s energy.

The wind’s energy can help aeroplanes to reach their destinations more quickly. A wind called the jet stream blows high above the Earth’s surface. If an aeroplane flies in the same direction as the jet stream, it acts as a tail wind. A journey across the Atlantic Ocean takes around one hour less than if the aeroplane flies against the jet stream.

 

 

 

 

 

 

The winds of a tropical cyclone cause great damage.

Tropical cyclones (also called hurricanes or typhoons) are some of the most powerful winds on Earth. They can have winds that travel up to 350 km/hour. Most hurricanes stay at sea, but some come ashore. Their winds destroy buildings and power lines. Hurricanes, such as the one that hit New Orleans in 2005, can cause widespread flooding.