Common medium-temperature concentrator
A parabolic trough uses a curved parabolic mirror to focus sunlight onto a linear receiver tube running along the focal line. The receiver contains a fluid—often oil or molten salt—that absorbs heat for power generation or process heat.
Typical uses and advantages:
- Utility-scale power plants: widely used in commercial concentrated solar power (CSP) plants for electricity production.
- Industrial heat: suitable for processes requiring temperatures in the medium range (up to roughly 400°C depending on the heat transfer fluid).
- Proven technology: mature supply chains and predictable operational characteristics.
Design characteristics:
- Single-axis tracking: troughs rotate about one axis to follow the sun, simplifying mechanics compared to dual-axis systems.
- Scale: modular rows can be added to grow plant capacity.
- Integration: pairs well with thermal storage systems to provide dispatchable power.
Limitations include sensitivity to diffuse light and the need for high DNI, but trough systems balance cost, reliability, and performance for many commercial projects.