Bifacial concentrator Ag‐free crystalline n‐type Si solar cell

Abstract

We report results obtained using an innovative approach for the fabrication of bifacial low-concentrator thin Ag-free n-type Cz-Si (Czochralski silicon) solar cells based on an indium tin oxide/(p + nn + )Cz-Si/indium fluorine oxide structure. The (p + nn + )Cz-Si structure was produced by boron and phosphorus diffusion from B-and P-containing glasses deposited on the opposite sides of n-type Cz-Si wafers, followed by an etch-back step. Transparent conducting oxide (TCO) films, acting as antireflection electrodes, were deposited by ultrasonic spray pyrolysis on both sides. A copper wire contact pattern was attached by low-temperature (160°C) lamination simultaneously to the front and rear transparent conducting oxide layers as well as to the interconnecting ribbons located outside the structure. The shadowing from the contacts was~4%. The resulting solar cells, 25 × 25 mm 2 in dimensions, showed front/rear efficiencies of 17.6-17.9%/16.7-17.0%, respectively, at one to three suns (bifaciality of~95%). Even at one-sun front illumination and 20-50% one-sun rear illumination, such a cell will generate energy approaching that produced by a monofacial solar cell of 21-26% efficiency.

Flexible and Semi‐Transparent Ultra‐Thin CIGSe Solar Cells Prepared on Ultra‐Thin Glass Substrate: A Key to Flexible Bifacial Photovoltaic Applications

“…For further investigation of bifacial applications, the PV parameters of the STUT CIGSe solar cells on SLG and UTG were measured under more realistic and practical conditions considering a typical environmental albedo effect. [ 55,56 ] Assuming 1‐sun illumination with typical albedos of around 20–30% of incoming light, the total light intensity that a solar cell receives will be around 1.2–1.3 sun including 1‐sun from the front and 0.2–0.3 sun from the bottom, independently. However, owing to the simulation limitations of exact and additional 0.2–0.3 sun from the rear side, the performance of the STUT CIGSe solar cells was measured under 1.18 sun and 1.31 sun, which consisted of 1‐sun from the front side by a solar simulator and 0.18 or 0.31 sun from the rear side by controlling the number of LED bulbs close to the natural light spectrum under a sample stage with separate calibration of the light intensities.…”

A review of concentrator silicon solar cells

“…The structure of the cell is shown in Fig. 9 [66], the highest front and rear illuminated efficiencies of the cell which was made using N-type wafer were 17.6-17.9% and 16.7-17% under 1-3 suns [67], the front and rear illuminated efficiencies of the cell which was made using P-type wafer were 18.6-19% and 14.9-15.3% under 1-5 suns [68].…”

Performance Analysis of Triple‐Cation Mixed‐Halide Bifacial Perovskite Solar Cell with 17% Rear and 25% Front Efficiency

“…[ 9 ] Absorption loss at the rear end and the minority carriers’ diffusion lengths are important factors affecting the back‐side contribution of bifacial SCs, the minority carriers’ lifetimes, the absorber layer's thickness, as well as the albedo coefficient of the background surfaces. [ 10 ] There is usually a metallic grid pattern on the front surface of a conventional monofacial SC, which allows the front surface to become transparent. On the backside of the monofacial SC, however, there is an opaque metal film.…”