Category Science

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.

Have you ever had your hat blown off by the wind? Has a strong gust of wind ever made you lose your balance? If so, then you have experienced the energy of the wind. People have used the wind’s energy for thousands of years.

This boat uses sails to catch the wind’s energy.

The earliest human use of wind energy was for sail-boats. The ancient Egyptians used sails to catch the wind and move boats along the River Nile around 6,000 years ago. The first windmills were made in Persia (now Iran) around 1,400 years ago. Windmills and wind turbines use the wind’s energy to turn machinery. Windmills grind grain or pump water. Today, wind turbines create electricity.

This early wind turbine, built in 1897, made electricity from the wind’s energy.

In 1887, the first wind turbine was built for generating electricity. It was not very efficient. A Danish man called Poul la Cour improved the design in 1897. By 1918, Denmark had enough wind turbines to produce around three percent of the country’s electricity.

A wind farm uses giant turbines to turn the wind’s energy into electricity.

Today, the wind is mainly used to generate electricity known as wind power. The energy of the wind is collected by a wind turbine and converted into electricity for use in homes, businesses and schools. Wind turbines are normally built in clusters known as wind farms.

Wind is the movement of air in the atmosphere from one place to another. Wind can move at different speeds and strengths. Wind can be warm or cold. The movement of the wind makes the clouds move and changes the weather.

The Earth’s atmosphere is made up of areas of high and low pressure. These are caused by differences in the temperature of the air and the Earth’s surface. Areas of high pressure push air towards areas of lower pressure. This movement of air is what we call wind.

This weather scientist (meteorologist) uses a floating balloon to measure the wind.

Meteorologists study winds around the world. The trade winds blow towards the Equator from the north-east in the Northern hemisphere and the south-east in the Southern hemisphere. Where these winds meet around the Equator, there is an area of low pressure and gentle winds called the doldrums. The Westerlies are also trade winds flowing west to east.

Monsoon winds blow across southern Asia. They are powerful and bring heavy rainfall. In India, farmers rely on the monsoon winds and rain for their crops.