The solar spectrum is separated by an optical filter, and just part of the spectrum is sent out to the PV cells for electrical power generation. The remainder of the spectrum, which cannot be used by the solar batteries, is directed to a thermal absorber to produce thermal energy. Credit: Gan Huang, Kai Wang and Christos N. Markides
Solar energy is among the most plentiful renewable resource sources, and reliable solar innovations have terrific possible to ease the grand difficulties of increasing international energy needs, while minimizing associated emissions. Solar energy can pleasing the electrical and thermal-energy requirements of varied end-users by methods of photovoltaic (PV) and solar thermal (ST) innovations, respectively. Recently, hybrid photovoltaic-thermal (PVT) ideas have actually been proposed that synergistically integrate the advantages of PV and ST innovations, and can producing both electrical power and beneficial heat all at once from the very same location and element.
Spectral splitting is an emerging technique for developing high-performance PVT solar batteries, which utilize sophisticated styles with optical filters that direct various parts of the solar spectrum either to the PV cells for electrical power generation or to a thermal absorber for heat generation. Nevertheless, the supreme effectiveness limitations of spectral-splitting PVT (SSPVT) collectors depending upon the application and end-user needs, in addition to the optimum collector styles, PV cell and optical filter products that can allow us to approach these limitations have actually stayed uncertain, with an absence of agreement in the field, encouraging a more detailed evaluation of these elements of SSPVT innovation.
(a) Physical design of a perfect focusing SSPVT collector. (b) Limit of overall effectiveness for various PV cells with various bandgap energies in various applications. (c) Optimal spectral-splitting filters for typical PV cell products. Credit: Gan Huang, Kai Wang and Christos N. Markides
In a brand-new paper released in Light Science & Application, Christos N. Markides and Gan Huang from Imperial College London in the UK, in cooperation with Kai Wang from Zhejiang University in China, report a thorough structure for forecasting the efficiency of such collectors, which is then utilized to recognize their effectiveness limitations, and to supply in-depth assistance for choosing optimum PV products and optimum spectral-splitting filters efficient in providing a combined thermal and electrical efficiency that approaches the effectiveness limitations of this innovation.
“We found that the relative value of thermal energy to that of electricity has a significant influence on the total effective efficiency limits, the optimal PV cell material and the optimal spectral-splitting filter of SSPVT collectors.”
“CIGS solar cells are considered particularly promising for SSPVT collector applications owing to their adjustable bandgap energy. The optimal lower- and upper-bounds of the spectral-splitting filter depend strongly on the PV material” they included.
“Detailed maps in our research can assist designers in selecting appropriate solar-cell materials and spectral-splitting optical filters, depending on the conditions and application, in order to achieve optimal overall performance accounting for both energy vectors (electricity and heat) generated by these systems.” the researchers mentioned.
Reference: “Efficiency limits of concentrating spectral-splitting hybrid photovoltaic-thermal (PV-T) solar collectors and systems” by Gan Huang, Kai Wang and Christos N. Markides, 5 February 2021, Light: Science & Applications.
DOI: 10.1038/s41377-021-00465-1
Funded by the UK Engineering and Physical Sciences Research Council (EPSRC), the Imperial College London EPSRC Impact Acceleration Account.
