PV Gap

Edwin Said:

Explain how solar cell produces electricity.?

We Answered:

photovoltaics (PV) are the direct conversion of sunlight into electrical power.

Let's take a look at what a solar PV system comprises of, then we'll explain how the solar panels work.

Solar Power Generation Systems begin with the solar module. Solar modules capture solar energy and generate direct current (DC) electricity. Inverters (power conditioners) convert DC into AC (alternating current) to run many common appliances and equipment.

Photovoltaic means electricity from light.
A solar PV system uses the natural energy from daylight in the form of solar radiation to generate electricity. This is different technology to solar thermal systems used for heating and hot water.


A charge is placed across the cell and as the energy from the sun hits the silicon, an electron is released from the atom. Due to the charge across the cell, this electron then flows towards the positive layer. Once you have an electron flow, a current is generated. This direct current is converted by an inverter in the system to an alternating current (AC) at the same level as the national grid.
I hope this helps
David
at www.solarcells101.com

Terrence Said:

How heat is converted to electricity using a solar collector or cell?

We Answered:

The traditional solar electric panels that people generally think of don't use heat to generate electricity.

A concentrating solar collector, on the other hand, does use heat to generate electricity. It focuses the sun's heat onto a tube containing a fluid like oil. That fluid gets extremely hot and generates steam. The steam in turn turns a turbine to generate electricity. These are not generally used for residential systems, they are very effective in commercial scale systems.

For more details, see http://www.nrel.gov/learning/re_csp.html…

Dale Said:

Which solar wavelengths are converted to electricity?

We Answered:

The answer is non-trivial. The cell will convert photons beyond its band-gap into electric current but it will not convert all the energy of the photon. Indeed the shorter the wavelength, the less of the energy will be converted and the lower the efficiency at that wavelength. And then you have to keep in mind that shorter wavelengths can not penetrate the material as well as long wavelengths and there is a loss of quantum efficiency in the blue.