Solar thermal powers systems are those which use concentrated solar energy in order to produce the high temperature heat which is needed for generating electricity by collecting and focusing on sunlight. Due to all solar thermal power systems have solar energy collectors with two main components; they can capture and focus sunlight onto a receiver.
There is a heat transfer fluid which is heated and circulated in the receiver in order to produce steam in most of these types of systems. Then, this steam is converted into mechanical energy in a turbine that could power a generator in order to produce electricity.
These solar thermal power systems have equipped with tracking systems which is helpful in keeping sunlight focused onto the receiver throughout the day as the sun changes its position in the sky.
Types of Solar Power Thermal Systems: These are three main types of concentrating solar thermal power systems:
(1) Linear Concentrating Systems: They are efficient in collecting the sun’s energy by using long, rectangular and curved mirrors. These mirrors focus on sunlight onto receivers which is able to run the length of the mirrors. The fluid is heated by the concentrated sunlight which is flowing through the tubes. In order to boil water, the fluid is sent to the heat exchanger in the conventional steam turbine generator for producing electricity.
A linear concentrator system has a number or field of collectors in the parallel rows which are aligned in an orientation in order to maximize solar energy collection. Through this, the mirrors are enabling to track the sun form east to west during the day and it concentrates sunlight onto the receiver tubes.
(2) Solar Power Towers: In order to reflect and concentrate sunlight onto a receiver on the top of the tower, this system uses a large field of flat and sun tracking mirrors which are heliostats. Sunlight can be concentrated efficiently as some power towers use water as the heat transfer fluid.
The thermal energy storage capability helps the systems in order to produce electricity at the time of cloudy weather or at night.
(3) Solar Engines: This system use a mirrored dish which is similar to a very large satellite dish and in order to reduce the cost, this mirrored dish is composed of many smaller flat mirrors formed into a dish space. This surface directs and concentrates sunlight onto a thermal receiver that can absorb and collect the heat engine can be used in engine systems.