SOLAR POWER SYSTEMS EXPLAINED

Ever since 1954, when scientists at Bell Telephone discovered that silicon–an element found in sand–created an electric charge when exposed to sunlight, solar technology has evolved and been adopted by more than 2 million homes throughout the country. Today, solar panel systems provide a very attractive option to homes and businesses as a clean, affordable energy choice.

Solar panel systems: the basics

We can now harness the energy of an infinite source of power–the sun–thanks to the creation of solar panels. Solar panels work in the following way:

Solar cells in your solar panels absorb the energy from the sun during the day.
The energy is collected and converted into direct current (DC) energy by circuits within the cells.
The DC electricity is converted to the useful alternating current (AC) electricity that comes out of your wall outlets by a device called an inverter;
This means you may use it in your home, store it in a solar battery, or send it back to the grid.

We’ll go over solar panel systems and the equipment you’ll need to generate electricity from the sun in the sections below. Are you already an expert on how solar panels work? Great! Continue reading in our Solar 101 area, or move on to the next part to learn about the advantages of solar power.

What is a solar panel?

A solar panel is a device that absorbs sunlight and converts it to electrical energy. Solar panels typically consist of solar cells (silicon-based), wiring, a metal frame, and a glass cover. Solar panels are typically four feet broad and six feet tall.

What components make up a solar panel system?

The installation of solar panels is a simple process. Solar panel systems have only four primary components and no moving parts, making them simple to install and maintain. A solar panel system is made up of four parts:

Solar photovoltaic panels–to convert solar energy into electricity
Inverters–to convert DC electricity into AC electricity
Racking and mounting systems–to affix your solar panels to your roof (or to the ground, depending upon your installation type)
Performance monitoring systems–to track and monitor the output and health of your solar panels and inverters

Solar panels are made up of a series of silicon solar cells coated in glass and held together by a metal frame, with wiring and electronics in and behind the cells to collect the electrical current that flows out of the cells. Each solar panel, also known as a solar module, measures around 4 feet by 6 feet and weighs about 30 pounds.

The “active” component of a solar panel, despite the lack of moving parts, is the silicon solar cells themselves: when sunlight strikes the silicon solar cells, it activates electrons, which begin to flow through the cell. The flow of electrons is captured by wires in the cells, which are then mixed with the output of other cells in a solar panel. Check out our post on the subject for a more in-depth look at how solar panels and solar cells work.

Solar cells are often available in 60 or 72 cell configurations. However, many firms are experimenting with new techniques to improve the effectiveness of solar cells at converting sunlight into electricity current, so you’ll see a lot of “half-cut” solar panels now, where each cell is chopped in half, resulting in a solar module with double the number of cells (i.e., 120 or 144).

Not all panels are created equal

There are a number of factors to consider while looking for the best solar panels for your home and budget, including product quality, durability, and long-term performance. In Nexergy’s guide for solar, you may learn more about how to evaluate solar panels.

Inverters

Solar panels use cells to gather the sun’s energy and convert it to direct current (DC) electricity. However, alternating current is used in most homes and businesses (AC). The DC electricity from solar panels is converted into usable AC electricity by inverters. String (or centralized) inverters and microinverters are the two most common types of solar inverters. Power optimizers can be added to string inverters to make them work like a microinverter system.

String (or centralized) inverter

Your complete array of solar panels is connected to your electricity panel by a single inverter. String inverters are often the cheapest inverter option, and they’re a very robust technology that’s been the most widely used inverter kind in the past. Multiple strings of panels can be linked to one inverter; however, if the electricity generation of one of the panels in a string reduces (as it may due to shade), the performance of the entire string will be temporarily reduced.

Microinverters

When you choose microinverters, one is (generally) installed at each solar panel, allowing each panel to produce as much as possible. Microinverters will reduce performance concerns if parts of your panels are shaded at different times of the day or if they aren’t all mounted facing the same direction. Microinverter prices are typically higher than string inverter prices.

Power optimizers:

Power optimizer systems are a cross between micro-inverter and string inverter systems. Power optimizers, like microinverters, are put at each panel. The optimizers, on the other hand, “condition” the DC electricity before transferring it to a centralized inverter, rather than transforming it from DC to AC. When one or more panels are shaded, or if panels are mounted facing different directions, they operate well, just like microinverters. Power optimizers are more expensive than string inverters, but less expensive than microinverters.

Racking and mounting systems

The pieces of hardware that secure your solar panels to your roof or the ground are known as solar racking and mounting systems.

Solar panels should face south and be positioned at a 30 to 45 degree angle to work at their best (depending on how far you are from the equator). Panels facing east or west with a pitch angle of five degrees or more will still function properly, but will produce 10 to 20% less electricity than those installed under optimum conditions. Most roof-mounted solar systems for homes are “lie-flat” systems, which means the solar panels’ pitch matches the pitch of your roof. In some cases, though, you can use racking to tilt or position your panels at an angle that is best for capturing the sun’s rays.

There are two types of mounts: fixed mounts, in which the panels remain stationary, and tracking mounts, which allow panels to “follow” the sun as it moves across the sky during the day (single-axis track mounts) and during the changing seasons (dual-axis track mounts). Tracker mounts are only suitable for ground mounted solar.

Performance monitoring systems

Performance monitoring systems give you detailed information about your solar panel system’s performance. You may measure and track the quantity of electricity your system produces on an hourly basis with a monitoring system.

The most commonly used inverters in the domestic market all come with production monitoring apps, allowing you to keep track of your panels’ output. In some circumstances, the app will also give consumption tracking to help you keep track of your overall solar panel savings. Note that this additional consumption monitoring may incur a fee.

Monitoring your solar panel system will help you spot any performance concerns and guarantee that you get the most out of your solar panel system in terms of power production–and financial rewards!

The following are the two main types of monitoring systems:

On-site monitoring: A monitoring device is installed on your property and records the quantity of electricity used.
Remote monitoring: Your solar PV system sends data about its performance to a monitoring provider that you may check online or on your phone.