Spectral beam splitting is a promising method to achieve high efficiency solar energy conversion. Its potential applications include multi-junction PV receivers, hybrid collectors and even biomass production. Although spectral splitting receivers can achieve high theoretical conversion efficiencies, they have not yet evolved to the commercial level. In this paper, we provide a review on the recently published research in this field and discuss the drawbacks associated with practical applications. Suggestions are made which we believe will lead to improvements in optical efficiency (including geometrical limitations) and the fabrication costs of spectrally splitting solar receivers.

Spectral beam splitting for efficient conversion of solar energy - A review

A review of the concentrated photovoltaic/thermal (CPVT) hybrid solar systems based on the spectral beam splitting technology

Thermal improvement of linear Fresnel solar system utilizing Al2O3-water nanofluid and multi-way twisted tape

Thermodynamic and optical analyses of a hybrid solar CPV/T system with high solar concentrating uniformity based on spectral beam splitting technology

A review on the development of photovoltaic/concentrated solar power (PV-CSP) hybrid systems

Thermodynamic and optical analysis for a CPV/T hybrid system with beam splitter and fully tracked linear Fresnel reflector concentrator utilizing sloped panels

Spectral selective transmission coatings can adjust the spectrum of incident solar radiation to reduce the waste heat generation in solar cells and to improve solar photovoltaic conversion efficiency. The ideal spectral transmissivity of the coatings should match the spectral response of solar cells, which means the ideal spectral transmissivity should be equal to 1.0 in the range of the spectral response and 0 in the other spectrum. The reflection performance of the three kinds of spectral selective transmission coatings for silicon solar cells are designed and analyzed. The results indicated that the ZnS/Na3AlF6 coating systems have a wider reflected infrared (IR) region than the TiO2/SiO2 coating systems, but lower transmissivity in the wavelength range of 0.5 μm to 1.1 μm. Furthermore, an Nb2O3/SiO2 coating system is proposed and optimized, which has 31 layers with a smaller total thickness of 2.675 μm. The radiative properties including reflectivity and transmissivity of spectral selective transmission coatings are investigated and theoretically analyzed.

Theoretical Analysis of Spectral Selective Transmission Coatings for Solar Energy PV System

Thermodynamics analysis was carried out for solar thermal receivers with different selective coatings. The relation between the energy conversion efficiency of a medium-high temperature solar thermal system, the spectral properties of selective coating and the operating temperature of the receiver were discussed. Furthermore, the relation between the optimum operating temperatures, the exergy efficiencies and the incident solar flux were analyzed for the traditional concentrating system and concentrating beam splitting system, respectively. According to the analysis results for the thermal receiver with blackbody surface and selective coatings, the optimum cutoff wavelength was obtained for the ideal selective coating. An analysis method for the optimum operating temperature calculation was developed for thermal receivers with selective coating. The optimum operating temperature for an actual selective coating was analyzed on the basis of the proposed theory.

Thermodynamic analysis on medium-high temperature solar thermal systems with selective coatings

The invention relates to a solar concentration and frequency division photovoltaic photo-thermal comprehensive utilization device which comprises a concentrator, photovoltaic assemblies, spectral frequency dividers, a thermal receiver and a secondary reflector. The concentrator comprises a plurality of plane glass mirrors and a concentrator frame, the plane glass mirrors are arranged obliquely, and the concentrator frame is arranged at an inclination angle theta2; the plane glass mirrors are obliquely focused on surfaces of the photovoltaic assemblies mounted above the concentrator frame; the photovoltaic assemblies are mounted at inclination angles theta1; the photovoltaic assemblies and the thermal receiver are respectively arranged on upper sides and lower sides of the spectral frequency dividers; and the secondary reflector is arranged below the thermal receiver. The solar concentration and frequency division photovoltaic photo-thermal comprehensive utilization device has the advantages that problems of overheating of the surface of a concentrator solar cell and uneven distribution of energy flow on the surface of the concentrator solar cell are solved, and the conversion efficiency of a cell and the energy efficiency of a thermal utilization portion are improved.

Solar concentration and frequency division photovoltaic photo-thermal comprehensive utilization device

The utility model relates to a solar energy light-concentrating and frequency-dividing photovoltaic photo-thermal comprehensive utilization apparatus comprising a light concentrator, a photovoltaic assembly, a light spectrum frequency divider, a heat receiving device, and a secondary reflecting mirror, wherein the light concentrator consists of multiple plane glass mirrors which are arranged in an inclined manner and a light concentrator frame which is arranged at an inclined angle theta2, the plane glass mirrors focus on the surface of the photovoltaic assembly in an inclined manner, the photovoltaic assembly is installed above the light concentrator frame, the photovoltaic assembly is mounted at an inclined angle theta1, the photovoltaic assembly and the heat receiving device are respectively arranged at the upper side and the lower side of the light spectrum frequency divider, the secondary reflecting mirror is arranged right below the heat receiving device. The solar energy light-concentrating and frequency-dividing photovoltaic photo-thermal comprehensive utilization apparatus is characterized in that the problems of cell surface over heat and uneven surface energy flow distribution in a light-concentrating solar cell are solved, and cell converting efficiency and available energy efficiency of a heat utilization part are improved.

Yang Liu

Papers

Thermodynamic and optical analysis for a CPV/T hybrid system with beam splitter and fully tracked linear Fresnel reflector concentrator utilizing sloped panels

Theoretical Analysis of Spectral Selective Transmission Coatings for Solar Energy PV System

Thermodynamic analysis on medium-high temperature solar thermal systems with selective coatings

Solar concentration and frequency division photovoltaic photo-thermal comprehensive utilization device

Solar energy light-concentrating and frequency-dividing photovoltaic photo-thermal comprehensive utilization apparatus