Parabolic Trough
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A parabolic trough is a type of solar thermal energy collector. It is constructed as a long parabolic mirror (usually coated silver or polished aluminum) with a Dewar tube running its length at the focal point. Sunlight is reflected by the mirror and concentrated on the Dewar tube. The trough is usually aligned on a north-south axis, and rotated to track the sun as it moves across the sky each day. Alternatively the trough can be aligned on an east-west axis, this reduces the overall efficiency of the collector but only requires the trough to be aligned with the change in seasons, avoiding the need for tracking motors. Heat transfer fluid (usually oil) runs through the tube to absorb the concentrated sunlight. The heat transfer fluid is then used to heat steam in a standard turbine generator. The process is economical and, for heating the pipe, thermal efficiency ranges from 60-80%. The overall efficiency from collector to grid, i.e. (Electrical Output Power)/(Total Impinging Solar Power) is about 15%, similar to PV(Photovoltaic Cells) and less than Stirling dish concentrators.

Current commercial plants utilizing parabolic troughs are hybrids; fossil fuels are used during night hours, but the amount of fossil fuel used is limited to a maximum 27% of electricity production, allowing the plant to qualify as a renewable energy source. Because they are hybrids and include cooling stations, condensers, accumulators and other things besides the actual solar collectors, the power generated per square meter of space ranges enormously.
The PS10 solar power tower near Seville concentrates sunlight from a field of heliostats on a central tower.A solar power tower consists of an array of flat reflectors (heliostats) that concentrate light on a central receiver atop a tower. Focusing is critical and the reflectors track the sun through the day and the year on two axes. A working fluid (air, water, molten salt) flows through the receiver where it is heated up to 1500 °C before transferring its heat to a power generation or energy storage system. Power towers are less advanced than trough systems but they offer higher efficiency and better energy storage capability. The Solar Two in Daggett, California and the Planta Solar 10 (PS10) in Sanlucar la Mayor, Spain are representatives of this technology.

A solar bowl consists of a fixed parabolic reflector that concentrates light onto a receiver which tracks the focus of light as the sun moves across the sky. One has been constructed in Marseilles, France and another in Auroville, India.

Concentrating Photovoltaic (CPV) systems convert concentrated light into electricity by PV rather than heat engines. They also use tracking systems, mirrors, and lenses to achieve high concentration ratios and are able to reach efficiencies above 40%. [66] A solar power station planned for Victoria, Australia will use heliostat concentrating PV technology similar to the power tower concept