# Solar Energy Information

Make It Solar Science Fair Projects

## 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

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:

Atotal = A1 + A2

Atotal = 1.8 A + 1.8 A = 3.6 A and

Power = 1.5 V x 3.6 A = 5.4 Watts

### Batteries in Series

In series the voltage is additive and the amperage is constant.

Vtotal = V1 + V2

Vtotal = 1.5 V + 1.5 V = 3.00 V and

Power = 3.00 V x 1.8 A = 5.40 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

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:

Atotal = A1 + A2

Atotal = 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

In series the voltage is additive and the amperage is constant.

Vtotal = V1 + V2

Vtotal = 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.