What is a Solar Array? (2024)

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Leonardo David is an electromechanical engineer, MBA, energy consultant and technical writer. His energy-efficiency and solar consulting experience covers sectors including banking, textile manufacturing, plastics processing, pharmaceutics, education, food processing, real estate and retail. He has also been writing articles about energy and engineering topics since 2015.

Tori Addison is an editor who has worked in the digital marketing industry for over five years. Her experience includes communications and marketing work in the nonprofit, governmental and academic sectors. A journalist by trade, she started her career covering politics and news in New York’s Hudson Valley. Her work included coverage of local and state budgets, federal financial regulations and health care legislation.

A solar array is a group of solar panels wired together to create an electrical power output. You combine a solar array with other components, such as an inverter and battery, to complete a solar system.

The best solar installers can help you determine the number of solar panels you need in an array to generate enough power for your home. Read on to learn more.

A solar array consists of multiple panels wired together to produce enough energy to power your home. The most efficient residential solar panels have a rated power output of around 350 to 400 watts (W). However, the output of a single panel is minimal compared to a home’s energy needs.

According to the U.S. Energy Information Administration, a typical home uses 10,632 kilowatt-hours (kWh) or energy per year. Even with favorable sunshine conditions, a 360 W panel only generates around 450 kWh to 600 kWh of energy annually. But you can use multiple panels to reach a higher energy production.

An array allows you to wire multiple solar photovoltaic (PV) panels together and utilize the combined electricity production. Your solar installer will conduct a detailed assessment of your home’s energy needs and sunshine conditions to determine your ideal solar array size.

Solar panels generate direct current (DC), which you must convert into alternating current (AC) to power your home appliances. Solar systems convert this power using an inverter, and the type of inverter you use determines the wiring of your array. There are three main types of solar inverters:

You can work with a solar installer to determine the best inverter for your solar PV system.

Three main factors determine how many solar PV panels you need in your array:

You can use our step-by-step guide to determine how many solar panels you need for your property.

You can increase the size of an existing solar array, but there are some technical considerations. If your solar array uses a string inverter, you can only add more panels if the inverter is below maximum capacity. If the existing inverter cannot handle more panels, you have two options:

Expanding a solar array with microinverters is much simpler — since each panel is equipped with its own inverter, you do not need to worry about power conversion capacity. However, you must make sure the AC circuit used by the microinverters is not overloaded. If the existing circuit cannot support more panels, you will need another inverter to expand your system.

Solar cell technology is easily adaptable thanks to its modular design, meaning you can adapt solar panels to any project scale. A homeowner might install 15 to 20 panels, while a large-scale solar farm or power plant may have more than a million panels. In either case, PV modules are the basic building block.

Most home solar systems are composed of a single array, but there are cases where it can make sense to split your installation into multiple groups.

If you own a large property, a solar company may identify several areas with adequate sunshine conditions. Generally, you can split solar arrays into several units with a common inverter to take advantage of different roof sections. However, wiring solar panels together is not cost-effective if there is a long distance between each grouping. In this case, installing separate solar panel arrays could be a better option.

As previously mentioned, you can only expand an existing solar array if the inverter has the capacity for additional panels. If you want to expand an existing installation without replacing the inverter, you can simply add another solar array to your property.

Multifamily homes often have separate power meters and energy bills for each dwelling. When adding solar panels to a multifamily property, the simplest way to split savings is by separating the solar system into multiple arrays.

For example, if a property owner installs 40 solar panels on a two-family dwelling, you could split the system into two arrays with 20 panels each. Since there is no connection between the arrays, you would also split electricity bill savings by design.

The only way to connect a solar power system to the local power supply is by opting for a professional installation. You generally cannot obtain an interconnection permit for a DIY solar installation. We also do not recommend installing rooftop panels as a DIY project due to the risks of falling and handling high electricity voltages.

However, you can opt for DIY solar to power smaller projects, such as your camper. If you want to attempt an off-grid solar project, you can purchase solar kits specifically designed for DIY projects. These kits have lower voltages and wattages that are safe to handle.

Solar panels cost around $2.85 per watt, according to our March 2023 survey of 1,000 homeowners with solar. The National Renewable Energy Laboratory (NREL) reports a similar figure of $2.95 per watt. Your total array cost will vary depending on how many panels you have and the type of inverters you use but generally, the average system costs between $15,000 to $20,000.

You can claim solar incentives such as the federal solar tax credit to lower your system costs. Formally known as the Investment Tax Credit (ITC), the solar credit allows you to claim 30% of solar installation costs as a federal tax deduction. Depending on your location, additional solar incentives may be available.

The exact process of installing a solar array may vary depending on your chosen installer, location and utility company. Most solar projects follow these general steps:

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Most modern solar panels can last between 25 to 30 or more years with proper maintenance. The best residential solar panels include 25-year product warranties to maintain longevity during the lifetime of your system.

A solar panel is a device that uses multiple PV cells to collect sunlight and generate electricity. A solar array is a group of solar panels wired together, acting as a single energy source. Both solar panels and solar arrays use a renewable energy source — sunlight — to generate emissions-free electricity.

You can classify solar arrays based on the type of panels you use. There are three main types of solar panels: monocrystalline, polycrystalline and thin-film. Monocrystalline panels have the highest energy conversion efficiency and are the most common in residential installations. Polycrystalline panels are more cost-effective but have a slightly lower efficiency. Thin-film panels are not typically recommended for rooftop installations due to their low efficiency but are ideal for vehicles and other applications.

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