An international research collaboration has unveiled a groundbreaking design for Concentrated Solar Power (CSP) trough systems, proposing a paradigm shift that could significantly reduce land usage and operational costs. Traditionally, Trough CSP relies on large parabolic mirrors that track the sun's movement throughout the day, focusing sunlight onto a stationary receiver pipe. This new approach, detailed in the Journal of Solar Energy Engineering, reverses that dynamic: the parabolic mirrors remain stationary, while a smaller, more agile receiver pipe moves to capture the concentrated solar flux. This innovation holds substantial implications for the global CSP market, particularly as nations like China expand their solar thermal infrastructure.

The core of this novel design involves setting a small, slightly curved section of the parabolic mirror low on the ground, with its angle adjusted only seasonally for azimuth changes. The critical departure is the receiver, a narrow absorber pipe, which now traverses a circular path as the sun moves across the sky. The research team, comprising experts from the UK, China, and Finland, explored various receiver movement mechanisms, noting that while sliding offers lightness and potential cost savings, rotation provides superior accuracy and stability. Their paper, "Design and principle of novel linear solar concentrator with asymmetric parabolic reflector and independently movable receiver," highlights the technical feasibility and advantages of this system.

Song Yang, lead author from the UK, emphasized the profound impact of this design on land utilization. "In the current setup, we space large parabolic mirror arrays apart to prevent self-shadowing in the morning and late afternoon," Yang explained. "Sometimes, over 30% of the sunlight is lost just because of these gaps, wasting significant land. By eliminating nearly all the curve of the parabolic mirror and leaving only a small, almost flat section on the ground, we eliminate this shadow loss." This allows for much denser packing of solar units, maximizing energy yield per square meter.

The team developed a sophisticated mathematical model to predict system performance, focusing on the deviation angle between the sun's rays and the parabola's axis. Simulations indicated optimal results when the fixed reflector is aligned east-west and tilted to the local latitude, maintaining a small deviation angle for most of the year, which translates to superior sunlight concentration and higher efficiency. Prototype testing, utilizing an 850 mm parabolic mirror reflector and a 60 mm receiver pipe, demonstrated remarkable optical efficiencies of over 96%, peaking at 99% under ideal conditions, validating the simulation's accuracy.

By fixing the heavy, cumbersome mirrors in place and instead moving the lightweight receiver, the design significantly reduces the need for complex tracking mechanisms, motors, and associated maintenance. This directly translates to lower capital expenditure and reduced operational costs over the plant's lifespan. The ability to position units closer together also addresses a key challenge in large-scale CSP deployment: land availability and efficient land use. The researchers are now seeking funding to advance to the next phase, which will involve detailed examination of heat and liquid flow dynamics within the system, assessing its outdoor performance, and identifying further avenues for cost optimization.