Solar Panels Power plant uses sunlight to get energy. Since sunlight is abundant and renewable, it can be used to power homes and commercial premises. If you set up a solar power plant, you may need to spend upfront. However, it will significantly reduce your energy consumption.
Understanding Solar Energy
Solar energy is the radiant light and heat emanating from the Sun. It is harvested through a myriad of methods, such as photosynthesis in plants and solar heating.
Solar power panels rely on subatomic particles known as photons to produce electricity. These particles begin their journey in the center of the Sun, traveling through different layers before being released into space. The journey from the Sun’s center to the surface may take between 100,000 and 50 million years to complete.
Once the photons escape the Sun, it takes a little over 8 minutes for them to reach Earth, where they strike solar panels and initiate the photovoltaic effect.
The Photovoltaic Effect (How Solar Panels Generate Electricity)
The secret sauce of solar panels lies in their ability to convert photons into electrons. In essence, a solar panel converts photons into direct current, which is then converted into alternating current for use in domestic and commercial applications.
Solar cells are usually made of silicon, a semiconductor capable of generating electricity. When sunlight hits the panel, the photons interact with the silicon atoms, releasing electrons in a phenomenon known as the photovoltaic effect.
A solar cell is constructed with a positive and negative silicon sheet sandwiched together. An upper silicon layer is filled with phosphorus for a negative charge, and a boron-infused lower layer maintains a positive charge. The resulting field funnels the electrons toward the conductive metal and out of the panel.
So electricity has to flow somewhere. Once the photovoltaic process generates a current, Since the current produced by a solar panel is DC, it needs to be converted to AC before use in most situations. Once converted to AC, solar energy can be used in a variety of ways.
Access to a grid-tied system is the most common method. A grid-tied system draws a significant portion of its energy needs during the day from solar panels. Depending on the size of the system, more energy may be produced than the site needs, so surplus electricity is sent back to the grid. When the sun goes down, the consumer receives supplemental power from the utility.
While grid-connected systems are not entirely self-sufficient, they are an effective way to lower energy bills and do good for the environment.
A key advantage of a grid-connected system is the ability to sell surplus solar power back to the utility through a process called net metering. On cloudy days and during the night, the solar system may not produce enough energy to meet the demand. The opposite is true for very sunny days: when energy use is low but production is high, the panels will collect surplus energy, typically more than enough for the customer’s energy needs.
Net metering measures the flow of electricity in both directions: how much energy a system draws from the utility, and how much energy is put out. When a solar panel system is over-producing, the meter actually runs backward, resulting in the utility company rewarding the credit for the surplus. Energy.
These credits can be used to buy energy from the utility when the solar system is not able to meet the demand.
Make Up the Components of the Solar System?
Solar panels are the most obvious component of a photovoltaic system, but only represent about 30% of the total system cost. The high-tech flicker of a solar panel is just the tip of the iceberg that a photovoltaic system uses to harness renewable energy from the sun.
Let’s take a closer look at the key components that make up the solar system.
Solar Photovoltaic Panels
A typical solar panel contains silicon cells, a metal frame, wiring elements, and glass. An insulating layer and a protective back sheet protect the panels from excessive heat and humidity.
While the general construction of solar panels is fairly standard, silicon cells are produced in two different formats:
Monocrystalline: The cells are a single solid silicon crystal. Mono cells offer more space for electrons to flow, resulting in a smaller, more efficient panel. The downside is that they are more expensive.
Polycrystalline: The cells are made of many separate pieces of silicon melted together. While not as efficient as mono cells, poly cells tend to cost less.
Mono and poly cell serve the same purpose. Aesthetics and budget will help you determine which is the right fit for your next project. Mono panels have a darker, more uniform color, while poly panels are lighter (typically blue). If the site is space-limited, mono panels may be the way to go thanks to their high efficiency. But if space is not an issue or you are up against a tight budget, poly panels are still an excellent option.
Solar panel energy comes directly from the panel in the form of direct current. But the energy needs to be converted into alternating current before it can be used in the commercial electric grid. Thankfully, DC is easily converted to AC, leaving the work for an inverter.
Inverter is classified into 4 broad categories:
Stand-alone Inverter: Receives DC energy from batteries charged by solar panels and does not interact with the grid.
Grid-tie inverters: Match the electric current from the solar panels to the utility. Grid-tie inverters shut down during power outages, so they can’t be relied upon for backup power.
Battery Backup Inverters: Receive energy from the battery and export excess energy to the grid. Battery backup inverters are capable of delivering AC power during a power outage.
Intelligent Hybrid Inverters: These are all-in-one solutions that can be used for grid-tie, stand-alone, or backup applications. Intelligent hybrid inverters are often connected directly to a solar array and manage solar load, battery storage, and grid interaction.
Racking and Mounting System
Racking and mounting hardware do much more than secure panels to a roof or ground – they provide the right position for maximum sun exposure. Choosing the correct mounting configuration and position is essential to ensuring maximum output from any system.
Solar panel racking and mounting systems come in 3 categories:
Ground Mount Systems: Traditional ground mount systems anchor stacked panels into the ground, often two to four panels high. Two rails typically support each panel, which can be oriented in either a portrait or landscape position. These systems are attached to the ground with steel rods, screws, or ballasts such as concrete blocks.
Tracking System: Motorized tracking systems follow the Sun throughout the day, maximizing exposure to sunlight. Tracking systems are further classified as single-axis or dual-axis. Single-axis systems follow the Sun in a straight line from east to west. The dual-axis system tracks the sun in a circular pattern for better exposure to sunlight.
Roof Mounting Systems: The most common roof mounting systems use a rail that is securely mounted to the roof. Other roof-mounted systems attach the panels directly to bolts or screws mounted into the ceiling, eliminating the use of rails and providing a more sleek aesthetic and lighter weight. Ballasted and non-penetrating systems are typically used on flat roofs or terraces that cannot support the mounting hardware.
Performance Monitoring Systems
A performance monitoring system is a dashboard that provides a complete picture of the performance of your system. Aside from the fuzzy feelings of watching your meter wind up in reverse, a solar performance monitoring system provides valuable insight into a photovoltaic system.
A performance monitoring system provides information about energy production and consumption, optimizes energy use, and can notify you of problems in your solar panel system. Solar monitoring systems work with inverters, usually through monitoring software that drives the connection between the inverter and other devices.
The performance monitoring system gathers information as the inverter converts direct current to alternating current and makes that information accessible to the homeowner via companion apps and smart home devices. Best performance monitoring systems collect data through a central inverter or from individual microinverters connected to each solar panel. The latter option provides greater insight into the performance of individual solar panels and allows for faster diagnosis of potential problems.
How Are Solar Panels Made?
The basic solar panel setup hasn’t changed much in recent decades. Like the arrays that first appeared in homes decades ago, most modern solar panels are still made of a silicon matrix sandwiched between a glass plate in front and a polymer sheet in the back.
Solar panels have to withstand severe weather conditions during their more than 25-year life. The best solar panels are engineered to withstand the test of time, requiring a few basic materials and careful manufacturing standards.
Solar panels are best described as a silicon and glass sandwich. The ingredients that go into solar panels are relatively straightforward:
- Silicon Cell
- metal frame
- the glass
- 12-volt cords
- bus cable
Silicon, the element that gives solar panels their power-generating magic, is the active ingredient in the solar-panel-sandwich recipe and is also one of the most energy-intensive to produce. Silicon is one of the most abundant elements on Earth and a major component of beach sand. But converting the sand into pure silicon suitable for solar panels is an energy-intensive process that requires refining in high-temperature arc furnaces.
Once the silicon is refined the raw product is ready to be manufactured
The isolated silicon chunks are shaped into cylindrical ingots, with particular attention to proper atomic orientation. At this stage, boron is added to the silicon to give it a positive charge. Available space and energy demand are two important factors considered when designing solar systems. The ingots are then cut into thin wafers the thickness of paper, then treated with an anti-reflective coating to help them absorb sunlight better.
Next, conductive metals are added to each wafer’s surface. Phosphorus is spread across the surface, providing a negative charge to balance the positive charge of boron and allowing a controlled flow of electrons.
At this level, an individual solar cell is complete. Next, the cells are soldered with metal connectors into a matrix. This assembly is sandwiched between a protective back sheet and glass covering and is terminated with a junction box and frame.
How Are Solar Systems Designed?
Two important factors are considered when designing solar systems: available space and energy demand. All the nuts and bolts of solar system design depend on these two factors, so a thorough understanding of them is essential to a well-planned solar installation.
To begin with, a solar designer will calculate daily energy needs, usually by looking at the location’s utility bill. Next, the designer will determine the ideal number of solar panels for the project, and the available space to accommodate them. With the determination of energy needs and available space, a designer can begin shopping for components.
Designing a solar system can be complex. A designer must determine the requirements of the location, potential shade, optimal panel pitch/angle, required permits, and more. Software solutions can help in estimating solar energy needs and planning the best solar system.
For example, with only one energy bill, Aurora Solar’s design software automatically provides high-quality design and material recommendations for any given space. Aurora also provides a number of planning and design tools in one intuitive package, including site design, load profiles, shed analysis, automated system design, sales proposals, permit templates, and more.
Of course, having a complete understanding of how solar panels work is just the first step. Here are some additional resources if you want to learn more about solar and the solar industry:
- Now that you know how solar panels work, let’s take a look at the different types of panels on the market.
- See how solar panels are linked together – called “stringing” – to deliver electricity where it’s needed
- Interested in Battery Storage? Here’s a Primer for Everything You Need to Know About Storing Solar Energy
The Solar 101 section of our blog has many other resources, as well, to help answer all of your solar-related questions.
Schedule a demo and fast-track your next solar installation project today.