11 1 Solar Cells

How efficient are solar cells?

As a result, the power conversion efficiency (PCE) of this type of solar cells has increased from 3.8% to 19.3% in only 4 years, making them comparable in efficiency to the commercial crystalline silicon solar cells 14, 15.

When was the first solar cell invented?

The first silicon solar cell was developed at Bell Laboratories in 1954 by Chapin et al. . It already had an efficiency of 6% which was rapidly increased to 10%. The main application for many years was in space vehicle power supplies. 2.1.1. Status today Slow but steady improvement of conversion efficiency.

What is a big question mark for the future of solar cells?

2.1.2. The silicon supply problem A big question mark for the future is the source of highly purified silicon for solar cells. Fifty percent of the cost of a module is due to the cost of processed silicon wafers. The PV industry has in the past used reject material from the semiconductor industry that was available at low cost.

What are the requirements for the ideal solar cell material?

Requirements for the ideal solar cell material are: (1) band gap between 1.1 and 1.7 eV (2); direct band structure (3); consisting of readily available, non-toxic materials; (4) easy, reproducible deposition technique, suitable for large area production; (5) good photovoltaic conversion efficiency; and (6) long-term stability.

Are solar cells a complication?

A complication, however, arises from the fact that each subcell has to generate the same electric current in the case of the conventional two-terminal devices. Prominent examples of these tandem or multijunction solar cells are the a-Si/SiGe and the GaInP/GaAs/Ge technologies, the latter being used in space applications.

What reflects the quality of solar cells?

The fill factor is yet another important parameter that reflects the quality of solar cells.