The current reliance of the power sector on fossil fuels for power generation has significant environmental drawbacks. Burning these finite fuels releases greenhouse gases, a major contributor to climate change. However, sustainable energy sources, like wind and solar power, produce little to no emissions, helping mitigate climate change and air pollution. This article will explore the basics of a typical wind energy conversion system (WECS).

Why wind power?

Wind turbines generate electricity without burning fossil fuels, which means they don't produce greenhouse gases or other air pollutants. This helps combat climate change and reduces reliance on finite resources, as just explained. The cost of wind energy has fallen significantly in recent years, making it a competitive option compared to traditional forms of energy generation. It is a domestic resource, so countries aren't reliant on imported fuels. The manufacturing, installation and maintenance of wind turbines would also create new jobs and wind energy can be harnessed in remote locations where it might be difficult or expensive to build traditional power plants.

What comprises a basic WECS?

These systems harness the wind's kinetic energy and turn it into usable electrical energy. A WECS has several key mechanical and electrical components that allow it to produce electricity and includes systems that control the movement of its parts and the power that is being produced. The following is the summary of these components and systems:

Mechanical components:

• Rotor: The spinning part of a WECS with blades that capture the wind's energy.
• Main shaft: The shaft connects the rotor to the rest of the system, transferring the rotational energy.
• Gearbox (optional): Many turbines use a gearbox to increase the rotation speed of the main shaft, making it more efficient for electricity generation.
• Nacelle: This housing protects the gearbox, generator and other mechanical components at the top of the tower.
• Yaw drive: This mechanism rotates the nacelle to position the rotor directly facing the wind.
• Pitch control system: This adjusts the angle of the rotor blades to optimize wind capture and power generation based on wind speed and direction.
• Brakes: These are used to stop the rotor in emergencies or during maintenance.
• Tower: The tall structure that supports the entire WECS.

Electrical components:

• Generator: Converts the rotational energy of the main shaft into electrical energy.
• Converter: Converts the generator's output, usually direct current (DC), into alternating current (AC) compatible with the power grid.
• Transformer: Increases the voltage of the electricity for efficient transmission over long distances.

Control systems:

• Sensors: These measure wind speed, direction and other vital data to optimize turbine operation.
• Control systems: These computers use sensor data to adjust the pitch of the blades, yaw direction and other functions to maximize power generation and ensure safe operation.

Can WECS be installed in urban areas?

Traditional large-scale wind turbines with towering blades might not be ideal for cities, but wind power can still play a role in urban energy generation. For instance, the technology helps cities reduce reliance on fossil fuels and combat climate change, will contribute to a more decentralized and resilient power grid, and can generate electricity for streetlights, public transportation or other community needs.

However, large wind turbines have some limitations as cities are densely packed, making it difficult to find suitable locations for large, sprawling wind farms. The tall blades can pose a safety risk in close proximity to buildings and people, and urban environments can have turbulent and unpredictable wind patterns, affecting efficiency. However, smaller wind turbines such as vertical axis wind turbines and micro wind turbines can be used for producing electricity in urban areas. The vertical axis wind turbines are compact and have a spinning axis vertical to the ground. They work well in turbulent wind and can be mounted on rooftops or integrated into buildings. Similarly, micro wind turbines are even smaller versions suitable for individual homes or businesses, generating power for on-site use. Micro wind turbines can generate a range of power, typically between 50 W and 10 kW, according to the U.S. Department of Energy.

How can WECS be connected with grid?

The first step is to obtain the specific grid code from a local grid operator. These codes establish the technical requirements for connecting a WECS to the grid. They can vary depending on location and grid characteristics. The grid codes typically address factors such as:

• Power quality: Limits on voltage fluctuations, harmonics (distortions in the AC waveform) and power factor (ratio of real power to apparent power).
• Frequency response: The ability of the WECS to respond to changes in grid frequency and help maintain stability.
• Low voltage ride-through (LVRT): The capability of the WECS to stay connected to the grid during voltage sags or dips.
• Islanding protection: Mechanisms to ensure the WECS disconnects from the grid in case of an outage, preventing it from energizing isolated sections.
• Communication protocols: Specifications for data exchange between the WECS and the grid operator for monitoring and control purposes.

Conclusion

Renewable and dependable, wind power can help us satisfy our expanding energy demands without negatively impacting the environment. To generate power, a WECS relies on a number of essential mechanical and electrical parts. Its control systems also regulate the motion of its components and the output of power. In order to link it to the grid, one must acquire and adhere to the precise grid codes provided by a local grid operator.