PV Gap

Audrey Said:

How do solar cells work?

We Answered:

Detailed Version: A solar cell is composed of a semiconductor with n-type and p-type material, that has a built-in potential at the junction. When light photons hit the semiconductor, they are absorbed and convert the photons energy into an electron and hole pair. These carriers are split by the built-in electric field of the junction in the semiconductor which outputs a current and voltage that can be used for energy.

Less complicated version: light hits a solar cell and the light is converted into a voltage and current similar to a battery which can be used to supply electrical power.

Jenny Said:

How do solar cells work? What types are there?

We Answered:

http://science.howstuffworks.com/environ…
I typed your question into Google and there's loads of stuff.
Have a look at the link.

Jeremy Said:

How do Solar Cells Work?

We Answered:

Solar cells are a sandwich of N type and P type silicon. The N type has excess electrons (Negative) after the atoms have bonded and the P has a deficiency of electrons (Positive) to form bonds.

At the junction, it forms a depletion zone as electrons jump from the N type to the P type, this results in an electric field as electrons have moved to the P type, leaving it negatively charged.

Now light comes along and hits this depletion zone (the N layer at the top is transparent), the light gives energy to the electron which lets it leave the bond, this electron is attracted to the N type silicon (remember that the N type is positive after having lost electrons to the P type).
Now these electrons slowly get bunched up on the N type silicon and this electron pressure (voltage) is able to do work in an external circuit.

When it is connected to a device, electrons travel from the N type through the circuit and end up at the P type side, when this happens electrons form the P type jump back into the depletion zone ready to start the process over again.

So electrons are not LOST, they just get moved through the external circuit.

Have a read of http://www.howstuffworks.com/solar-cell.… for a more indepth explanation

Jenny Said:

How do Organic Solar Cells work?

We Answered:

The method is the same as that in a regular silicon solar cell. In other words, the material will be doped on one side of a junction to have extra electrons and on the other side to have fewer electrons. The junction will be set to absorb a specific wavelength of light. The difference is that the organic materials, or plastic etc. used for these types of cells will be much less expensive than silicon.

Crystal Said:

How efficiently do solar cells work with artificial light?

We Answered:

It depends on what sort of solar cell you are using. Different materials respond differently to different spectrums of light. If your talking about the solar cell in your calculator then I would assume its designed to work best under typical office or classroom lighting. However if your talking about the solar panels used to power houses or a solar car then I would assume they work best under the sun.

For a calculator I doubt that it matters what sort of light bulb you use.