An investigation into current challenges in solar cell technology

Abstract

Photovoltaic (PV) technology has a long revolution history that today we have three different generations: crystalline silicon solar cells (mono- and multi-crystalline silicon), conventional thin-film solar cells (amorphous silicon, CdTe, CIGS), and solar cells based on exploiting novel materials (organic solar cell, dye-sensitized solar cell, perovskite solar cell, quantum dot solar cell, and multi-conjunction solar cell). Each of them has unique advantages and challenges to face that need further research for solutions. Crystalline silicon solar cells have proved their dominance in the commercial PV industry by their matured and well-established manufacturing technologies, low prices, and high efficiencies; however, they are about to meet their efficiency limit. The most essential task for them now is to continuously increase efficiency as much as possible and reduce the costs. Second-generation thin-film solar cells offer low cost of production to manufacturers as they do not use semiconductor wafer substrates and their processing equipment requires lower process temperatures. Thin-film such as amorphous solar cells needs to shift to a new configuration (e.g., tandem, multi-junction) instead of staying in a single-junction structure as there are not many opportunities for them to boost efficiency. CdTe and CIGS need to recycle in the next 10 years as they contain toxic and rare elements. Organic and dye-sensitized solar cells are well known for their environmental friendliness but poorer efficiency than other PV types. Besides how impressive and rapidly developed perovskite solar cells are, they are also raising concern about the toxicity of Pb once they are commercialized. Multi-junction solar cells have surpassed the Shockley–Queisser efficiency limit thanks to their superior performances, and they keep progressing in combining materials to achieve a new efficiency record. This thesis will go into deeper these challenges and more to find out possible solutions of them.