Solar cells is the most common label we use on the equipment we use to produce electricity from sunlight. The power output is presented as Wp (Watt photo voltaic).
As each cell only generates approx. 0.5 V, the cells are connected in series. Doing so then gives a rough 30 V from a panel consisting of 60 cells. Normally they are grouped as 3 times 20.
Panels are mostly built up by 54, 60 or 72 cells.
The cell will degenerate over time. Calculate a 1-2 % decrease per year. Most manufactorer s offer a 90% warranty after 10 years and 80 % at 15 years.
The cell type is designated by the type of silicon, polycrystalline or monocrystalline. Monocrystalline are more expensive and also comes with a higher efficiency.
The expected lifespan is now 25-30 years (minimum).