Solar arrays are collections of solar panels and are increasingly popular among homeowners who seek to lower their energy costs. The larger the array, the more electricity panels will produce, and the lower energy costs will drop. Read on to learn more about how solar arrays work and how to choose the best size and setup for your home.

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What Is a Solar Array?

A solar array is a group of solar panels that work together to produce electricity. Each panel, or module, contains dozens of connected photovoltaic (PV) cells that absorb sunlight to generate energy. PV panels are modular, so you can buy more panels for a bigger array or invest in fewer for a smaller array.

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How Does a Solar Array Work?

Solar arrays harness the power of sunlight using silicone semiconductors. The silicone absorbs energy from the sunlight and transfers it into electrons, which flow to metal grid lines along the PV cell and then continue to an inverter.

The inverter converts solar cells’ direct currents (DC) to an alternating current (AC) that home appliances use. Your solar array can power your home’s electrical system, feed energy into the local electric grid, or send energy to a storage battery for future use.

Necessary Components of a Solar Array System

A complete blueprint for solar panels must include the following:

• Inverter: The inverter converts the electrical current from DC to AC before sending it to your home or the power grid. Systems may use a single inverter for the entire array or microinverters for each module.
• Mounting structure: This framework supports and secures the PV panels, providing stability and durability. It also positions the solar array at specific angles to maximize sun exposure.

Many systems also include the following:

• Storage: Certain types of batteries store solar energy, so you can use it at night when solar arrays are not producing energy. Solar storage can help homeowners and utility companies better manage any excess energy produced by residential solar arrays.
• Tracking system: The most efficient solar panels use a tracking mechanism that adjusts the panels throughout the day to follow the sun. Some systems allow movement along a single axis (east-west), while others enable dual-axis tracking.

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How To Determine Size

The first step in installing solar panels is determining how large your solar panel array should be. Follow the steps below to determine how much energy you need and the number of panels you need to install, whether you plan to hire a professional or take the do-it-yourself (DIY) approach.

Define the Goals of Your Solar Array System

Start by identifying what you want from your new solar array system. Here are a few examples:

• Achieve energy self-sufficiency. Some homeowners aim to meet their own energy needs without any help from the grid. This requires a large solar array and a storage system to ensure continuous electrical power. 
• Generate surplus energy to sell. Some power companies allow homeowners with a PV system to sell excess energy back to the grid. This requires a solar panel system large enough to produce more energy than you consume, plus a compatible inverter or storage system.
• Reduce your reliance on the grid. You can shrink your electric bill and carbon footprint without going completely off-grid. A moderately sized solar array can replace some of the electricity you purchase from your local power plant with clean, renewable energy.

Your goals will determine whether you choose a grid-tied system, an off-grid system, or a hybrid system. Weigh the benefits of purchasing your own solar panels against other solar power options, such as leasing equipment or entering a power purchase agreement.

Calculate the Watts Needed

Once you know what you want from your system, you can determine your monthly energy needs. Add up your last 12 months of electricity bills to determine the number of kilowatt-hours you used, divide that figure by 12 to get your average monthly usage, then multiply that figure by 1,000 to convert the kilowatts to watts.

This is a good time to invest in a home energy audit to identify potential energy-saving upgrades. You can perform a DIY energy audit or ask your power company for recommendations. The more efficient you can make your home, the cheaper your solar panel installation will be.

Track How Much Sunlight You Get

Next, factor in exposure to sunlight. The sunnier your area, the more productive your solar panels will be. Look up how many hours of peak sun your area gets per day, then multiply that number by 30 to get a monthly figure for a general estimate.

You can calculate the total power output you need from your system once you have a rough estimate of how many hours of peak sunlight your solar panels will encounter each month. Simply divide your monthly energy consumption by the hours of sun you recorded. Compare the answer to the energy production of individual panels to determine how many panels you’ll need to generate the wattage your household requires.

Consider Future Needs

Consider future needs or potential changes to your household. An electric vehicle or home addition would increase your electricity needs, for instance, while a new energy-efficient heating, ventilation, and air conditioning system would decrease your consumption.Weigh the cost of solar panels. Remember that purchasing a PV system could qualify you for certain state and federal incentives, such as the Residential Clean Energy Credit. Knowing which tax credits are available and when they expire will help you offset your installation costs.

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Best Arrangement and Placement for Solar Arrays

South-facing rooftops are the best place for solar arrays in North America. Ground-mounted solar arrays are also a viable alternative for many homeowners.

Below are a few factors to consider to determine the proper placement.

• Accessibility: Ground-mounted panels are easier to clean and maintain but more susceptible to accidental damage, theft, and vandalism.
• Air circulation: Ground- or pole-mounted panels allow for better air circulation, which keeps panels cooler and more efficient on hot days.
• Local restrictions: Review any homeowners association rules and local zoning regulations that might affect your solar panel installation.
• Roof condition: Consider the age and condition of your roof. Replace your roof before installing solar panels if your roof is near the end of its life span.
• Sun exposure: The azimuth (orientation) and tilt of panels play huge roles in the panels’ capacity for energy production. Choose a sunny area when determining where to install panels, orient them southward, and tilt them at an angle equal to your latitude.

The best solar companies can help you determine the ideal spot for your panels and walk you through different options.

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Our Conclusion

A well-planned solar array can be a smart investment to reduce grid reliance or achieve total self-sufficiency. Careful sizing and placement will ensure that your new system meets your current needs and leaves room for future changes. We recommend gathering recommendations and quotes from several top solar companies for optimal safety and efficiency.

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FAQ About Solar Arrays

How big is a 1 megawatt (MW) solar array?

A 1 MW solar array is big enough to power about 173 homes and will take up between five and 10 acres of land, according to the Solar Energy Industries Association. An array of this size is often called a solar farm and produces far more energy than a single home needs.

Can I install my own solar array?

You can install your own solar array, but hiring a professional is a better idea. Installing solar panels requires technical knowledge, adherence to local building codes, and electrical expertise.

How many solar panels make an array?

Any number of solar panels can make an array. An array can include as few as two panels or as many as hundreds or thousands. 

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