Wind Turbine
A wind turbine is a device that converts the kinetic energy of wind into electrical energy. Hundreds of thousands of large turbines, in installations known as wind farms, now generate over 650 gigawatts of power, with 60 GW added each year. They are an increasingly important source of intermittent renewable energy, and are used in many countries to lower energy costs and reduce reliance on fossil fuels.
Benefits of wind power
- Clean, abundant and inexhaustible fuel: Wind power produces no emissions and is not depleted over time.
- Local economic development: Wind plants can provide a steady flow of income to landowners who lease their land for wind development.
- Modular and scalable technology: utilities can use wind resources strategically to help reduce load forecasting risks.
- Wind energy is one of the cheapest of the renewable technologies while reducing reliance on imported fuels.
- Energy price stability: it reduces dependence on conventional fuels that are subject to price and supply volatility.
The disadvantage
most electricity use is in urban areas and the best wind resources are often far away.
Wind turbine come in
2 configuration
Horizontal Axis Wind Turbine (HAWTs)
Most wind turbines used today are horizontal axis machines. To work effectively they must face the wind by using a tail that automatically orientates the turbines or by using motors to move the turbine
Vertical Axis Wind Turbines (VAWTs)
Vertical axis turbines are cross-flow devices.
It will work with wind from any direction. They
are however less efficient at harnessing wind
energy.
It will work with wind from any direction. They
are however less efficient at harnessing wind
energy.
Effect of number of blades
- Wind turbines with large numbers of blades have highly-solid swept areas and are referred to as high-solidity wind turbines.
- Wind turbines with small numbers of narrow blades are called low-solidity wind turbines.
- In theory the more blades a wind turbine rotor has, the more efficient it is. However large numbers of blades can interfere with each other. High solidity wind turbines tend to be less efficient overall than low solidity turbines.
- Three bladed rotors tend to be most energy efficient.
Building Mounted/integrated wind turbines advantages
- Height advantage without the need for large towers.
- Disturbed flows around buildings can locally increase wind speeds.
- Energy yields may therefore be increased relative to open sites.
Ducted wind turbine
Ducted wind turbine is a preferred building type which is positioned on top of high buildings to catch high wind speeds and avoid obstructions.