What are Solar Arrays
A solar array is a group of solar panels connected together as part of your home solar system. In this guide, you'll learn what exactly a solar array is, how it differs from a single panel, and how to determine the right array size based on your location, roof conditions, and household energy consumption.
What Exactly Is a Solar Array?
A solar array is created when multiple solar panels are connected together in a series or parallel configuration. Just like a single book versus a bookshelf of books, one panel works alone while an array combines several panels to generate more power.
Most residential solar arrays contain between 10 to 30 panels, depending on the home's energy needs and available roof space. These panels are arranged strategically to capture the most sunlight - typically facing south in the Northern Hemisphere, and installed at an angle matching your location's latitude to optimize sun exposure throughout the year. In addition to direction and angle, panels in an array are also spaced properly to avoid shading each other, ensuring each panel performs at its best to maximize power generation.
While the array is a critical part of your solar power system, it's just the sunlight-capturing component and works alongside other equipment like inverters and mounting hardware to power your home.
How Solar Arrays Differ from Solar Panels
A solar panel is a single unit that converts sunlight into electricity through its solar cells, while a solar array consists of multiple panels connected together in a specific arrangement. The biggest difference lies in their power generation capacity - a typical solar panel produces between 250-400 watts of power, whereas a residential solar array can generate several kilowatts by combining multiple panels.
Installing solar arrays require more complex planning than installaing single panels, as factors like wiring configuration, panel spacing, and overall layout must be carefully considered for optimal performance. Most importantly, solar arrays can be designed to match specific power needs by adding or adjusting the number of panels, making them the practical choice for powering homes and businesses.
How Does a Solar Array Work?
A solar array works similarly to a single solar panel, both harnessing sunlight and converting it into usable electricity through photovoltaic (PV) cells. These cells are made of semiconductor materials that absorb sunlight, creating an electric field that pushes electrons through the material, generating an electric current. When sunlight hits a solar panel, the PV cells generate direct current (DC) electricity. This DC electricity is then sent to an inverter, which transforms it into alternating current (AC) electricity, the type used in homes and businesses.
However, a solar array combines multiple panels which means more surface area to capture sunlight and can generate more electricity.
The efficiency of both a panel and a solar array can be affected by factors like shading, temperature, and panel quality. However, with modern technology like optimizers and microinverters, solar arrays can maintain higher efficiency. Solar arrays last as long as individual panels, typically 20-25 years.
Determining the Right Solar Array Size for Your House
For typical homes, the number of solar panels needed depends on factors like the size of the home, its energy usage, and the local climate. A 1500 sq. ft. home, for example, typically uses about 6,000 kWh per year. A standard solar panel generates roughly 300 watts, or 0.3 kW, per hour under optimal sunlight. Based on this, you would need around 20 solar panels to cover the majority of your energy needs. For a 1800 sq. ft. home, you might need 24-25 panels, while a 2000 sq. ft. home could require 28-30 panels. These numbers are rough estimates, and your specific requirements may vary based on factors like the local climate, roof orientation, and energy efficiency.
Homes in sunnier areas such as California and Arizona require fewer panels than those in regions with frequent cloud cover or long winters. The orientation and pitch of your roof also play a crucial role; south-facing roofs in the northern hemisphere typically capture more sunlight, requiring fewer panels to meet energy needs. Additionally, the energy efficiency of your home influences panel requirements. Homes with better insulation and energy-efficient appliances will use less power, potentially reducing the number of solar panels needed.
For a more accurate calculation, it’s best to consult with a professional solar installer.
| State | Average Peak Sun Hours | Anuual Energy Consumption | Solar Array Size Needed | Panels Number Needed(300W) |
| California | 5.5 - 6.5 | 6000 kWh | 6 kW | 12 |
| Texas | 5.5 - 6.0 | 7200 kWh |
7.2 kW |
14 |
| Illinois | 4 - 4.5 | 7800 kWh | 7.8 kW | 16 |
| New Jersey | 3.5 - 4.0 | 8100 kWh | 8.1 kW | 20 |
Where's the Best Spot for Your Solar Array?
For roof installations, orientation and tilt are the primary factors. Ideally, solar panels should be placed on a south-facing roof to maximize sun exposure throughout the day. If that’s not possible, east or west-facing roofs can still work, but they might generate slightly less energy. If your roof is flat, a roof-mounted solar racking system can be installed to tilt the panels at the optimal angle. It’s essential to ensure that the roof is structurally sound and can handle the weight of the panels and mounting equipment.
Ground-mounted solar panels offer more flexibility compared to roof-mounted systems. South-facing ground mounts are still ideal, but the key advantage here is that you can adjust the tilt angle of the panels more easily than on a roof. For example, you can set them at an angle that is perfect for your location’s latitude or adjust them seasonally. During winter, when the sun is lower in the sky, it’s best to tilt the panels at a steeper angle, around 30 to 45 degrees to catch the sunlight as it comes in at a lower angle. In summer, a shallower tilt is more effective for capturing direct sunlight. If space allows, tracking systems can be installed, which follow the sun across the sky for even more energy efficiency.
If you’re installing on a shed, ensure the roof is strong enough to support the weight of the solar panels and that there is no obstruction casting shadows on the array.
How Much Does a Solar Array Installation Cost?
In the United States, solar array installation costs average around $2.85 per watt before incentives. For a typical American home needing a 6kW to 10kW system, you're looking at a total investment of $17,100 to $28,500.
But what exactly are you paying for? The largest portion goes to the solar arrays themselves, costing about $1.00 per watt. Next comes the inverter at $0.70 per watt - this crucial component converts the solar energy into usable electricity for your home. The remaining costs include mounting hardware ($0.35 per watt), professional installation labor ($0.50 per watt), and electrical components like wiring ($0.30 per watt).
Here's the good news: the actual cost you'll pay is significantly lower. Thanks to the federal solar tax credit, which covers 30% of your installation costs, plus various state and local incentives, your final cost could drop to between $12,000 and $20,000.
While this might still seem like a substantial investment, consider the long-term savings: the average household saves $100-$200 monthly on electricity bills, depending on local utility rates and sunshine exposure. This means you could recover your initial investment in just 5-8 years. After this break-even point, your solar array essentially produces free electricity for the next 15-20 years of its 25-30 year lifespan, potentially saving you $30,000-$50,000 over time.
Is Installing a Solar Array Worth It?
Whether a solar array is worth installing depends on several critical factors. First, your electricity consumption and local utility rates - if you're paying over $100 monthly for electricity, particularly in states with high rates like California or New York, solar arrays can offer significant savings.
Second, your roof's condition and sun exposure - an ideal roof should be in good repair, face south or southwest, and receive 6+ hours of direct sunlight daily without shade from trees or buildings. Third, your local climate and weather patterns affect solar production - though panels work even in cloudy areas, they're most efficient in sunny regions.
Fourth, available incentives in your area - some states offer additional tax breaks and rebates beyond the federal tax credit, making the investment more attractive. Finally, your long-term housing plans matter - you'll need to stay in your home for at least 5-8 years to recoup the investment.
You're likely a good candidate if you meet most of these criteria and own your home. However, solar arrays might not make financial sense if you're planning to move soon, have a heavily shaded or deteriorating roof, live in an area with very low electricity rates, or face strict homeowners' association restrictions.
Final Thoughts
A solar array is a system of multiple solar panels that work together to capture sunlight and generate electricity for your home. The size and efficiency of your solar array depend on factors like your home's energy usage, roof orientation, and the amount of sunlight your location receives. The cost of installing a solar array varies based on system size and location, but long-term savings on electricity bills can make it a worthwhile investment.
FAQ About Solar Arrays
1. How long do solar arrays last?
Solar arrays generally last 25 to 30 years. While their efficiency may slightly decrease over time, most systems continue to generate electricity well beyond their warranty period with minimal maintenance.
2. What is the difference between a solar panel and a solar array?
A solar array refers to a system of multiple solar panels connected together to generate more power while a solar panel is a single unit that captures sunlight and converts it into electricity. A solar array is typically installed to meet the energy needs of a household or business.
