Spectral solar panel (Patent pending) Alexander Zhivich, Ph. D. Visiting professor Framingham State University, Framingham, MA USA Address for correspondence: A. Zhivich, 17 Haskell St. Westborough, MA 01581 e-mail: email@example.com ; firstname.lastname@example.org phone: 1 508 847-7797 (cell) 1 508 836 3334 (home) We describe in this presentation a new design of solar panel – spectral solar panel - using any type of photovoltaic solar cells including semiconductor photovoltaic solar cells, perovskite solar cells, dye-sensitized solar cells, organic solar cells, quantum dots solar cells, and any other type of solar cells that could absorb in different areas of the solar spectrum – UV, visible and IR. The main concept of this new design lies in dispersion of solar light (e. g. by passing the solar light through the optical prism) first and then conversion of different spectral parts of the solar spectrum by several photovoltaic cells that are sensitized to (or absorb) that corresponding part of the solar spectrum. Since the losses of light energy in the course of light dispersion in prisms are negligible this new design of solar panels will significantly enhance the efficiency of light to electricity conversion. Technology for production of optical elements including all kinds of prisms from polymer materials is very well known and widely used. Thus, it is possible to produce the layer of solar cells sensitive to different parts of the solar spectrum on a suitable base material and then cover it by a polymer prism layer that will accomplish the solar light dispersion process correspondingly. Spectral solar panels produced according to this method could be successfully used for very efficient incident solar light to electricity conversion. Spectral solar panels should be installed using solar tracking system. Calculations showed that implementing the new spectral solar panels design with multiple solar cells as described above can reduce the losses of absorbed solar energy to heat from ~38% (silicon solar cell) to ~ 3.5 – 4%. That makes spectral solar panels ~1.5 times more effective than silicon solar cells in terms of incident solar light to electricity conversion.
Advantages of using the spectral solar panels:
1. Simple design that enables easy and cheap production.
2. Possibility of combination of different types of photovoltaic cells including but not limited to semiconductor photovoltaic solar cells, perovskite solar cells, dye-sensitized solar cells, organic solar cells, quantum dots solar cells, and any other type of solar cells that could absorb irradiation from different parts of solar spectrum (UV, visible, and IR) in one final device.
3. Much higher efficiency (more than 1.5 times higher verses silicon solar cells) of solar energy to electricity conversion (by means of conversion of different parts of solar spectrum to electricity by different solar cells sensitized to these specific parts of solar spectrum).
4. Wide selection of materials and designs for individual solar cells that are used to build the final solar panel.
5. Lack of the following problems that exist in multi-junction photovoltaic cells:
a) The upper semiconductor layers should be transparent for the light that should be absorbed by the next semiconductor layers. b) The selection of semiconductor band gap, absorption properties, and layer thickness of every semiconductor material used in multi-junction solar cell should allow for the current-matching in the stack design. Otherwise the transparent electrodes should be used for electricity harvesting from every p-n junction of the multilayer photovoltaic cell. c) Since the multi-junction solar cell has several semiconductor layers, intermediate layers, protective layers, and transparent electrodes, significant portion of light is reflected by the layer interfaces that eventually leads to significant losses in solar energy to electricity conversion efficiency especially in multi-junction photovoltaic cells with a large number of junctions.