What does the "fill factor" in solar cells indicate?

The fill factor is a critical parameter in assessing the performance and efficiency of a solar cell. It is defined as the ratio of the maximum power output of the solar cell to the product of its open-circuit voltage and short-circuit current. A higher fill factor indicates better quality and performance of the solar cell, as it means the cell is converting a larger portion of the light energy it receives into usable electrical power. This metric provides insight into the overall efficiency and effectiveness of the solar cell in converting solar energy into electricity, making it an essential factor for evaluating solar technology.

The other options address unrelated aspects. The aesthetic quality of a solar panel is more about its design and visual appeal rather than its performance. Manufacturing costs relate to the economics of producing solar panels and do not directly reflect their efficiency. Lastly, physical dimensions might affect installation or space considerations but do not determine the performance capability of the solar cells themselves.