Solar Concentrator Bio-Inspired by the Superposition Compound Eye for High-Concentration Photovoltaic System up to Thousands Fold Factor

Abstract

We have proposed a fruitful design principle targeting a concentration ratio (CR) >1000× for a typical high concentrating photovoltaics (HCPV) system, on account of a two-concentrator system + homogenizer. The principle of a primary dual-lens concentrator unit, completely analogous basic optics seen in the superposition compound eyes, is a trend not hitherto reported for solar concentrators to our knowledge. Such a concentrator unit, consisting of two aspherical lenses, can be applied to minify the sunlight and reveal useful effects. We underline that, at this stage, the CR can be attained by two orders of magnitude simply by varying the radius ratio of such two lenses known from the optics side. The output beam is spatially minimized and nearly parallel, exactly as occurs in the superposition compound eye. In our scheme, thanks to such an array of dual-lens design, a sequence of equidistant focal points is formed. The secondary concentrator consists of a multi-reflective channel, which can collect all concentrated beams from the primary concentrator to a small area where a solar cell is placed. The secondary concentrator is located right underneath the primary concentrator. The optical characteristics are substantiated by optical simulations that confirm the applicability of thousands-fold gain in CR value, ~1100×. This, however, also reduced the uniformity of the illumination area. To regain the uniformity, we devise a fully new homogenizer, hinging on the scattering principle. A calculated optical efficiency for the entire system is ~75%. Experimentally, a prototype of such a dual-lens concentrator is implemented to evaluate the converging features. As a final note, we mention that the approach may be extended to implement an even higher CR, be it simply by taking an extra concentrator unit. With simple design of the concentrator part, which may allow the fabrication process by modeling method and large acceptant angle (0.6°), we assess its large potential as part of a general strategy to implement a highly efficient CPV system, with minimal critical elaboration steps and large flexibility.

Experimental Analysis of Oscillatory Vortex Generators in Wind Turbine Blade

“…As efforts to conserve this remarkable species continue, it is likely that the peregrine falcon will continue to be an iconic symbol of the power and resilience of the natural world. Figure 4 shows the CAD design development and construction of the bio-inspired vortex generator with its dimensions in millimeters based on previous studies of peregrine falcon descent flight [9,11].…”

“…As efforts to conserve this remarkable species continue, it is likely that the peregrine falcon will continue to be an iconic symbol of the power and resilience of the natural world. Figure 4 shows the CAD design development and construction of the bioinspired vortex generator with its dimensions in millimeters based on previous studies of peregrine falcon descent flight [9,11]. These studies allow us to observe the elevation of six feathers on the back of the falcon, the addition of a linear arrangement of vortex generators with an axis of rotation, and then place this axis in the quarter chord of a blade with an s822 airfoil.…”

“…In wind energy systems, the use of vortex generators or VG devices on turbine blades and how these devices increase service life and power output is studied by research groups [5][6][7]. Previous studies of animals and plants try to mimic their morphological characteristics and add them to wind turbines, this process is known as bio-inspiration, Bio-inspiration can be defined in mechanical engineering as the creation of mechanisms based on living organisms [8][9][10][11]. For this reason, some works analyze species and how their special characteristics allow them to survive in their environment.…”

Experimental Validation of Double Paraboloid Reflection for Obtaining Quasi-Homogeneous Distribution of Concentrated Solar Flux

“…Several homogeniser configurations are well documented in the CPV field. For instance, prism-based, working on the principle of total internal reflection [10]; mirror-based, working on multiple reflections using several mirrored facets [9,[11][12][13]; or those that are lens-based, such as the Köhler homogeniser [14], or domed homogenisers, as in [15,16].…”