What is a Solar Panel?
Solar panels are devices that convert light into electricity, They are called solar panels because most of the time, the most powerful source of light is the sun. A solar panel is a collection of solar cells. Lots of small solar cells spread over a large area can work together to provide enough power to be useful, the more light that hits a cell the more electricity is produced.
Different types of Solar panels
Monocrystalline and Polycrstalline
The material differnce between polycrystalline and monocrystalline rests in the composition of the silicone substrate used to make solar cells, and in turn solar panels. As the name implies, monocrystalline means “a single crystal” while polycrystalline means many crystals.
Solar Panels also know as Photo Voltaic cells use some simple science to generate electricity.
Whether on a solar-powered calculator or an international space station, solar panels generate electricity using the same principles of electronics as chemical batteries or standard electrical outlets. With solar panels, it’s all about the free flow of electrons through a circuit.
Solar Panels – The basics
To understand how solar panels generate electrical power, it might help to take a quick trip back to high school chemistry class. The basic element of solar panels is the same element that helped create the computer revolution – pure silicon. When silicon is stripped of all impurities, it makes a ideal neutral platform for the transmission of electrons. This material is used to form the plates of solar panels.
Here’s where science enters the picture. Two plates of pure silicon would not generate electricity in solar panels, because they have no positive or negative charge.Panels are created by combining silicon with other elements that do have positive or negative charges.
Solar Panels – Creation of Electricity
In order for electricity to flow, a positive charge must also be created. This is achieved in solar panels by combining silicon with an element such as boron, which only has three electrons to offer. A silicon/boron plate still has one spot left for another electron. This means the plate has a positive charge. The two plates are sandwiched together , with conductive wires running between them. With the two plates in place, it’s now time to bring in the ‘solar’ aspect .
Natural sunlight sends out many different particles of energy, but the one we’re most interested in is called a photon. A photon essentially acts like a moving hammer. When the negative plates of solar cells are pointed at a proper angle to the sun, photons bombard the silicon/phosphorus atoms.
Eventually, the 9th electron, which wants to be free anyway, is knocked off the outer ring. This electron doesn’t remain free for long, since the positive silicon/boron plate draws it into the open spot on its own outer band. As the sun’s photons break off more electrons, electricity is generated. The electricity generated by one solar cell is not very impressive, but when all of the conductive wires draw the free electrons away from the plates, there is enough electricity to power low amperage motors or other electronics. Whatever electrons are not used or lost to the air are returned to the negative plate and the entire process begins again.
One of the main problems with using solar panels is the small amount of electricity they generate compared to their size. A calculator might only require a single solar cell, but a solar-powered car would require several thousand. If the angle of the panels is changed even slightly, the efficiency can drop 50 percent.
Some power can be stored in chemical batteries, but there usually isn’t much excess power in the first place. The same sunlight that provides photons also provides more destructive ultraviolet and infrared waves, which eventually cause the panels to degrade physically. The panels must also be exposed to destructive weather elements, which can also seriously affect efficiency.
Many sources also refer to these panels as photovoltaic cells, which references the importance of light (photos) in the generation of electrical voltage. The challenge for future scientists will be to create more efficient solar panels are small enough for practical applications and powerful enough to create excess energy for times when sunlight is not available.
Using solar power to travel is just one of the exciting new opportunities we may see in the near future and who knows, maybe someday soon you can take business class flights to and from South Africa using only solar power.
The use of solar panels can provide a useful addition to an overall energy efficiency strategy, by taking smaller appliances and products off the main power grid.
For more info on Solar Panels – watch the video.
With our conditions in South Africa providing plentiful sun in both summer and winter , solar panels are a no-brainer for anyone wanting to cut grid dependency.
Solar panels are going to become more affordable and efficient as the technology in design and manufacture improves.