Planar metasurface-based concentrators for solar energy harvest: from theory to engineering

Abstract

Solar energy is an inexhaustible renewable energy resource, which is a potential solution to global warming and aids sustainable development. The use of solar-thermal collectors to harness solar energy facilitates low-cost heat storage and can improve the stability of power grids based on renewable energy. In solar-thermal collectors, traditional concentrators, such as parabolic troughs and dishes, are typically used but inevitably require high-precise supports and complex tracking sun systems, which increase the cost of solar-thermal power stations and hinder their further applications. In contrast, planar meta-lenses (so-called metasurface-based concentrators) consisting of two-dimensional nanostructured arrays are allowed to engineer the frequency dispersion and angular dispersion of the incident light through delicately arranging the aperture phase distribution, thereby correcting their inherent aberrations. Accordingly, the novel meta-lenses offer tremendous potentials to effectively capture broadband, wide-angle sunlight without the extra tracking system. This review summarizes the research motivation, design principles, building materials, and large-area fabrication methods of meta-lens for solar energy harvesting in terms of focusing efficiency, operation bandwidth, and angular dependence. In addition, the main challenges and future goals are examined.

The Anomalous Reflection and Refraction of Metasurface in the View of Solar Concentrators

“…Tracking-free solar metasurface concentrators have been studied in China and the United States, with the U.S. Department of Energy conducting a project entitled "Dielectric [12] " and China's Key Special Project on "Broad-Band Planar Metasurface Solar Concentrators and Heat Collecting Systems" now underway. Although there is still a long way to go before metasurface solar concentrator systems can be applied at scale, we firmly believe that with the continuous progress of micro-nano processing technology, the large-scale application of metasurface concentrators will become a reality soon and trigger a new energy revolution [1] .…”

“…The efficiency of the concentrating system has a crucial impact on the power generation performance of the whole power generation system. The performance of traditional optical materials limits the efficiency of concentrating systems; the appearance of metasurface breaks the boundaries of the inherent properties of conventional materials and can be used in the future to solve this problem in the field of solar energy concentration [1] .…”

Polarization-multiplexing graphene-based coding metasurface for flexible terahertz wavefront control

“…In comparison, graphene has recently garnered significant attention due to its wide range of tunable conductivities, fast response speed, and polarization independence [29,30]. It has been extensively used to fabricate various tunable terahertz meta-devices, including reconfigurable specialized beam generators, tunable meta-lenses, controllable metacouplers, and so on [31][32][33][34][35][36][37][38][39]. Whereas, most existing graphene-based coding metasurfaces can only respond to a single polarization mode of the incident wave, which is considerably unfavorable for high integration and large capacity of terahertz communication [40][41][42][43].…”

The Effect of Height Error on Performance of Propagation Phase-Based Metalens

“…A metasurface, a kind of two-dimensional metamaterial, is composed of subwavelengthresolved meta-atoms that can be designed to enable multidimensional manipulation of the polarization, phase, and amplitude of the optical field [1][2][3][4][5][6]. By controlling the geometry, orientation, and composition of these meta-atoms, the metasurface can be used in a variety of applications, such as optical imaging, information processing, energy harvesting, and optical sensing [7][8][9][10][11][12][13][14][15][16]. As a typical application of a metasurface, metalenses provide an effective technical way to reduce the load of traditional optical systems, realizing the integration and versatility of optical systems.…”