Of all concentrating solar thermal power technologies, the parabolic trough is the most established at this time. But ever since the first CSP plants of this type have been constructed in the US in the 1980s, research and development of new and improved technologies has continued unabated.
The technological principle of all CSP is similar. The direct sunlight is captured and focused by mirrors. The concentrated thermal energy is then transferred to a medium and thereafter used for various applications, beginning with the generation of steam and ending with electricity production.
Because the parabolic trough is the most tried and tested variety of CSP today, it is also the technological and economic benchmark for up and coming alternative CSP solutions.