What are Photovoltaic (PV) Panels?

Photovoltaic Panels are are used to transform sunlight energy into electrical energy.  ”PV panel” is the common name for a photovoltaic panel.  Literally translated photovoltaic means "light-electricity".

Photovoltaic means "light-electricity".  It is formed from photo- which means light and -voltaic which means electrical current or electricity.
PV panels are made up of smaller sections called solar cells.  Solar cells, like batteries, each have a rated value of voltage (V or volts) and amperage (A or amps).  The total power in wattage (W or watts) delivered is the voltage times the amperage.
Volts x Amps = Watts or
V x A = W
Batteries can be arranged in parallel or in series depending on the requirements of the device we want to power.

Batteries in Parallel (large image)

In parallel the amperage is additive and the voltage is constant.  If we have batteries that are 1.5 V each and 1.8 A each then:
A_total = A₁ + A₂
A_total = 1.8 A + 1.8 A = 3.6 A and
Power = 1.5 V x 3.6 A = 5.4 Watts

Batteries in Series(large image)

In series the voltage is additive and the amperage is constant.
V_total = V₁ + V₂
V_total = 1.5 V + 1.5 V = 3.00 V and
Power = 2.25 V x 1.8 A = 4.05 Watts
How many of these batteries will you need and how will you have to arrange them if you want to power a 6 volt radio?

Solar Cells or Panels in Parallel (large image)

In parallel the amperage is additive and the voltage is constant.  If we have cells that are 0.5 V each and 0.1 A each then:
A_total = A₁ + A₂
A_total = 0.1 A + 0.1 A = 0.2 A and
Power = 0.5 V x 0.2 A = 0.1 Watts

Solar Cells or Panels in Series (large image)

In series the voltage is additive and the amperage is constant.
V_total = V₁ + V₂
V_total = 0.5 V + 0.5 V = 1.0 V and
Power = 1.0 V x 0.1 A = 0.1 Watts
Solar cells are connected and arranged into a single panel.  Some standard panel sizes are 12 volt and 24 volt.
How many of these cells will you need and how will you have to connect them to make a 12 volt solar panel?
If you have 2 panels that are rated at 12 volts each how many of them will you need and how will you have to connect them if you want a 24 volt system?
The terms "Solar Panel" and "Photovoltaic Panel" describe two different devices.  We use the terms as follows:
A Solar Panel collects and utilizes heat energy from the sun.
A Photovoltaic Panel transforms light energy into electrical energy.