What is photovoltaic solar power?
Basics of photovoltaic (PV)
The job of solar photovoltaics (PV) is to harness sunlight to generate electricity - which is solar energy or solar power. In order to do this, solar photovoltaic devices, called solar cell, are used, which are contained within solar panels, also called photovoltaic panels, or modules.
Understanding how photovoltaic systems generate electricity involves knowing the basics. In this article we cover:
Basics of photovoltaic
The solar PV module
How PV power is created
How photovoltaic technology is made possible
Applications of photovoltaic systems
“Photovoltaic” comes from two words: photons – the process of converting light to electricity – and voltage. Solar cell technology as we know it today has actually been around since the 1950s, when scientists created a practical, working solar cell made from silicon. Costs prevented mass commercialisation of the technology at first, but prices fell as cells gradually became more efficient at converting sunlight to generate electricity. In US the National Renewable Energy Laboratory focuses on the standards and principles of solar pv systems. National renewable energy laboratory does technical researches and documents summaries the technical needs of PV systems.
The solar PV module
Solar cells (these can be also called as photovoltaic cells and pv cells) are strung together, forming a photovoltaic module. You've no doubt seen the grids on PV solar panels. Solar cells are the individual cells within the module. Solar modules, or PV panels, are then connected to create the solar system.
Solar cells are small and capable of producing around 1 or 2 watts of power each. They're incredibly thin – about the thickness of four human hairs. They contain a material capable of conducting electricity once the sunlight provides solar energy. This material is typically silicon and acts as a semiconductor. By “semi,” we mean the material conducts electricity more than an insulator, but less than a metal.
How PV power is created
Photovoltaic energy is created via these steps by solar photovoltaics:
-
The semiconductor absorbs light and transfers that energy to negatively charged particles, called electrons.
-
The electrons flow through the semiconductor as electrical current – other solar cell layers extract the current from the semiconductor.
-
The current flows through metal contacts – the grid-like lines on a solar cell – before it travels to an solar inverter.
-
The inverter converts the direct current electricity (DC) to an alternating current electricity (AC).
-
The AC travels into the electric grid or, depending on the system, connects to the building's circuit.
You can learn more about inverters in our solar inverter guide. Also, get to know the other solar PV energy solutions you'll need in Types of solar equipment, explained.
How photovoltaic technology is made possible
In order to consistently generate photovoltaic solar energy year after year, photovoltaic solar panels (includes solar cells) have to withstand the outdoors. The ability to perform depends a lot on the photovoltaic materials, which must be durable and robust. We've already mentioned that the solar cells of a solar photovoltaic module consist of a silicon semiconductor. This semiconductor is enclosed by a protective material in a metal frame. The protective material is an encapsulant which consists of transparent silicon or a butyryl plastic and bonded around the solar cells. The solar cells are then embedded in ethylene vinyl acetate (EVA).
A polyester film – mylar is one example – is used for the backing. A glass cover or sometimes lightweight plastic encases the array, while the frame is steel or aluminium. Silicon bonds everything together. The bulk of the electronic parts are usually made from copper.
Solar cell to solar array
A solar cell module array (or pv arrays) is part of a photovoltaic solar panel system. What is an array in solar PV systems? It's a collection of solar photovoltaic PV panels. The solar panels are wired together to form one large-scale solar energy (or solar power) photovoltaic PV system. A solar PV array is usually associated with solar farms, but really, it's any grouping of connected modules to produce electricity.
Photovoltaic panel power output
Solar photovoltaic conversion of sunlight into usable solar energy is typically 20%. This means the photovoltaic panel output can, in theory, exceed 400 watts of power. The more efficient the panel is at turning sunlight into energy, the higher the output.
Most solar panels with 60 solar cells (this can be also called as photovoltaic cell) generate between 270 and 300 watts solar power. Let's say your panels will be in direct sunlight for five hours a day. Now let's use an example wattage from one solar panel with 60 solar cells at 290 watts of power. The calculation for estimating your solar energy output would be:
5 hours x 290 watts = 1,450 watts-hours, or 1.5 kilowatt-hours (kwh)
This translates to around 500—550 kWh of energy a year for each of your solar panels. This is how you can calculate the electricity generation of your photovoltaic systems. The solar pv installations can generate electrical power within their ability.
Applications of photovoltaic systems
Photovoltaic power is used for a variety of applications, either as a way to reduce one's carbon footprint, save energy costs to feed electrical devices with maximum efficiency or because an area is not served by power lines. Examples of how and where solar photovoltaic energy conversion systems are used include to help power the electric grid:
- Space satellites
-
Water pumps
-
Parks in remote regions
-
Remote residences
-
Telecommunication repeater stations
-
Navigational aids
-
Home appliances
-
Office equipment
-
Laptop computers
-
Supply of occasional power
-
Calculators and watches
-
Military uses, e.g., lightweight PV for charging electronic equipment in the field
However, as you can expect, the electricity consumers are not limited with those and solar power can supply electrical energy (or electrical output) for different purposes. The renewable energy may help to reduce the electricity generation costs. Solar technologies are the key part of the renewable technologies. PV panels are beneficial to generate electrical output and decreasing costs.
Benefits of pv systems and solar power can be summarized as efficacy and deliver of renewable energy. On the other hand, they have reduced installation costs and they are highly cost competitive. Most pv systems deliver big amount of electricity and help to improve the global capacity of energy. One of the main renewable energy sources is solar power and your solar pv system helps to deliver the energy efficiency you need for your applications.
Solar photovoltaic technology (or pv technologies) can help you to deliver low production cost and improve the efficacy of the electricity generated.
No matter what your application is, you can also learn more from our Quick guide: components for your solar PV system.
Download free CADs and try before you buy
Free CADs are available for most solutions, which you can download. You can also request free samples to make sure you’ve chosen exactly what you need. If you’re not quite sure which solution will work best for your application, our experts are always happy to advise you.
Whatever your requirements, you can depend on fast despatch. Request your free samples or download free CADs now.
Questions?
Email us at sales@essentracomponents.com or speak to one of our experts for further information on the ideal solution for your application 800-847-0486.