Look around you - on homes, commercial buildings, beside roads - solar panels are everywhere.
Even those handheld devices that don't need batteries are solar panels in their simplest form.
Panels have grown very popular for home use. While many governments have put in place incentives to encourage people to install their own solar energy electricity generators, price is still a significant factor.
It's really the return on investment that matters.
Ie: Total cost of the solar energy system divided by Actual savings each month = Months to recoup costs
This is often several years, which is why there is growing interest in people making their own panels - after all the parts are easy to source, the level of knowledge to undertake the project is not huge and it is a truly inexpensive solution that doesn't need high levels of skill to create.
So what actually is a photovoltaic cell?
A photovoltaic cell or PV cell as it is often called is a device that converts any available light directly into electricity. Generally, we think of the light source like the Sun but it need not be just the Sun. In fact, any light source will produce electricity. While the Sun is the best source, PV cells will produce electricity at night from street lights and the stars. Ie, they work 24 x 7 but at very low levels when the Sun doesn't shine.
The advantage of the Sun is it is very bright and allows the PV cell to produce maximum electricity for several hours per day.
A solar panel is a series of PV cells wired together. Each PV cell produces a small amount of electricity. Collectively the panel will produce an electrical output which is a function of the number of cells. The PV cells are encapsulated in a weatherproof surround and need to be aimed in the direction of the Sun.
So How Does the PV Cell Work?
PV cells are basically semiconductors made from silicon. When light strikes the cell, a certain portion of it is absorbed within the semiconductor material. The energy from the absorbed light is transferred to the semiconductor in the form of electrons being activated. The electrons are then allowed to flow freely.
PV cells all have one or more electric fields that act to force these electrons freed up by absorbed light to flow in a certain direction. This flow of electrons is an electrical current. By placing metal contacts on the top and bottom of the PV cell we can draw that current off.
Each PV cell has a rated wattage (volts x amps). The current, together with the cell's voltage (arising from the built-in electric field, define the wattage the solar cell can produce.
Notice that the activation medium is light - any light. The amount of flow is a function of the light intensity or energy, i.e, the more intense the light, the greater the flow.
Electricity will be created for however long the light source is available.
What is in the PV Cell?
Photovoltaic products are created making use of Gallium Arsenide which is processed and sliced into cells. A focusing device called a Solar Concentrator is placed across the cell to concentrate the light. These concentrators bend and focus the light over a specific point on the cell.
How much sunlight energy does our PV cell absorb?
PV cells are about 15 to 20 percent efficient, i.e., of the total light energy focused on the cell, about 15 to 20% of the energy is actually turned into electricity.
So there you have it. We have done the homework on solar panels. Check out our free newsletter - see our website details below. Thank you for reading our article. We trust you are ready to move towards your own solar panel project.