Central receiver system

Definition

A central receiver system, also known as a power tower, is a type of Concentrated Solar Power (CSP) technology that uses a large array of mirrors to focus sunlight onto a central receiver located at the top of a tall tower. This concentrated solar energy is then converted into heat, which is used to produce steam that drives a turbine to generate electricity. This system stands out for its efficiency and scalability in harnessing solar energy compared to other solar collector types.

5 Must Know Facts For Your Next Test

1. Central receiver systems are capable of achieving high temperatures, often exceeding 1,000 degrees Fahrenheit, which enhances their thermal efficiency.
2. These systems can incorporate thermal energy storage, allowing them to continue generating electricity even when there is no sunlight.
3. The design of central receiver systems enables them to have a smaller land footprint compared to other CSP technologies like parabolic troughs.
4. The mirrors in central receiver systems can be designed to automatically adjust their angle throughout the day for optimal sunlight capture.
5. Central receiver systems are typically used in utility-scale power plants due to their ability to generate large amounts of electricity efficiently.

Review Questions

• How does a central receiver system convert concentrated solar energy into electricity?
  • A central receiver system utilizes an array of heliostats to focus sunlight onto a central receiver located at the top of a tower. This concentrated sunlight heats a working fluid, typically water or molten salt, which is then converted into steam. The steam drives a turbine connected to a generator, producing electricity. The system’s design allows for efficient thermal energy conversion and high-temperature operation.
• What advantages do central receiver systems have over other types of solar collectors in terms of efficiency and scalability?
  • Central receiver systems generally offer higher thermal efficiencies compared to parabolic troughs or linear Fresnel collectors due to their ability to reach higher temperatures. They are also more scalable, making them suitable for larger utility-scale installations. Additionally, the integration of thermal energy storage in these systems allows for continuous electricity generation during non-sunny hours, enhancing their reliability as a renewable energy source.
• Evaluate the role of heliostats in the performance of central receiver systems and their impact on overall energy output.
  • Heliostats play a crucial role in central receiver systems by tracking the sun and reflecting sunlight towards the central receiver. Their design ensures maximum sunlight capture throughout the day, directly impacting the system's efficiency and overall energy output. An optimal arrangement and performance of heliostats can significantly enhance the amount of concentrated solar energy directed at the receiver, thereby increasing electricity production and making the system more effective in harnessing solar power.

Related terms

Heliostat: A device that consists of a mirror which moves to track the sun and reflect its rays towards the central receiver.

Thermal energy storage: A method that stores thermal energy for later use, allowing for electricity generation even when sunlight is not available.

Concentrated Solar Power (CSP): A technology that uses mirrors or lenses to concentrate sunlight onto a small area to produce heat, which can be converted into electricity.