Linear Concentrator

Introduction

Linear concentrators are a thermal type of power plant used for the generation of electricity. This type of power station belongs to the renewable (green) energy family and has recently seen a growth in usage due to rising coal prices and industry relevant technological advancements. Despite this, linear concentrators are relatively new and produce very little of the world’s total electrical supply (<0.2%). Linear concentrators do however show significant potential for wider application and further development.

Process Description

Sunlight is concentrated onto a central pipe positioned in the middle of a series of parabolic mirrors. The concentrated light heats the flowing heat transfer medium (thermal oil, water, etc.) that is flowing through the central pipe. It is possible to boil water directly then send the steam to the turbine, or, use the heat from thermal oil to heat water in a separate system which will then turn to steam.

The method described from this point onwards is for a system using thermal oil.

The hot thermal oil leaves the storage tank and passes through a steam generator (heat exchanger). Water is heated by the oil until it turns to steam. The steam is then sent to a steam turbine and the ‘cold’ thermal oil is returned to a storage tank.

Steam enters the steam turbine and causes it to rotate as it passes through the blades. The steam turbine is connected to an alternator via a gearbox and the alternator generates electricity. The steam is then condensed by a condenser and pumped back to the steam generator where it is again turned to steam.

Generated electricity from the alternator is distributed to an electrical transformer where the voltage is increased. The electrical current is then sent through an open air switchyard and into the national grid. Increasing the voltage reduces losses when the power is distributed through the national grid.

Modular cooling towers are used to cool the steam back to condensate. Cold cooling water is sent from the cooling tower to the condenser where it is heated by the steam. The steam changes state and becomes condensate. The ‘hot’ cooling water is then distributed to the cooling tower where the heat is passed to the ambient air.

3D Model Details

This 3D model shows all major components associated with a typical linear concentrator, these include:

  • Linear concentrator.
  • Hot thermal oil storage tank.
  • Cold thermal oil storage tank.
  • Pumps.
  • Steam generator.
  • Steam turbine.
  • Electrical transformer.
  • Turbine condenser.
  • Open air switchyard.

How Linear Concentrated Solar Power (CSP) Plants Work

The below video is an extract from our Mechanical and Electrical Engineering Explained Online Video Course.

 

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