How Many Solar Panels Do I Need?

Table of Contents

Are solar panels right for my house?

If you’ve been on a walk or a drive through your neighborhood, you’ve seen some neighbors with solar panels on their roofs in all manner of configurations. You can’t help but wonder, are solar panels right for my house? In southwestern states like Arizona, Nevada and Texas, chances are your home is ideally suited for solar panels. But from a technical perspective, there are several factors to consider. 

How to assess how many solar panels I need.

The size and shape of your home

If you’re a homeowner, you probably already know the square footage of your house. But the overall size of your roof will determine the upper limit on how many panels you can have. The more open surface area your roof has, the more solar panels you can fit. But more isn’t necessarily better. What is optimal for you will depend on your energy usage and savings goals. 

The quality of solar panels

Like any piece of technology, not all solar panels are created equal. There are a host of brands like QCell, REC, Hyundai, Canadian Solar, Longi, SILFAB, JA Solar and Jinko. These panels range in their capacity to produce wattage—typically from around 300W to 400W or more. Your energy consultant will assess how many watts you need to meet your savings objectives—given your roof size and average energy usage. A designer will calculate an optimal solution using these variables. 

Current electricity use

Most families see a similar schedule. They wake up early and prepare for work & school. They’re gone during the day, then are home, using energy during peak hours (between 4 PM to 8 PM) to run the A/C, cook dinner, wash clothes, turn on all the T.V.’s, and charge all the devices. Other homeowners see a steady, consistent use of energy throughout the day. These patterns of living will generate an energyuse graph that is unique to each household—and one that changes seasonally. A good solar provider will map out this usage by having a look at your energy bill and provide an optimal solution when it comes to calculating how many solar panels you need. An energy consultant may even recommend you add a solar battery to your system to offset peak energy costs.

The amount of sunlight

What may be the most obvious factor when assessing how many solar panels you need is how much sunlight your roof is getting. Your roof may be flat or angled. It may have a complex topography—or just two or three sides. If there are areas of your roof that create shade on adjacent areas, these spots may need to be avoided when designing the solar panel placement. Additionally, your home may be nestled between some tall trees that create shade on a portion of your roof. 

You may be wondering how can I measure the amount of sunlight my roof is getting exactly? Google actually developed a cool tool called Project Sunroof that uses satellite imagery and solar data to calculate exactly this! You can enter your address below to see the solar potential of your home. 

The size of the solar panels

No matter what your roof looks like, chances are there is a solar panel and a proper configuration that’s right for it. Solar panel sizes range from compact designs (approximately 40×20 inches) to the standard, more common designs of roughly 69x40 inches. Some homeowners will opt not to have panels on the roof and instead use a ground mount. If your property has a lot of extra space and perhaps gets more sun than the roof due to shading from trees, you may choose to go with a larger format solar panel design (approximately 78×39 inches) to maximize solar production. 

Factors that affect solar panel output efficiency.

Your solar energy consultant will also have a look at how your home is positioned relative to the sun. Does your roof have two faces—one pointing north & the other pointing south? Do the faces point east & west? Depending on your home’s geography, there will be optimal directions to position the solar panels. This will affect the panels’ output & efficiency throughout the year.  

Your solar system will contain more than just solar panels. Other technology, like the inverter system, will play a role in determining the panel output. There are two types of inverter systems: a string inverter system and a micro-inverter system. On the older, centralized, string inverter system, an individual panel’s drop in efficiency can affect the production of the overall system. For example, a single panel may experience shade, an obstruction like leaves or snow, or even a defect. These instances would cause your whole system to produce less wattage. On a micro-inverter system, the problem is isolated to the individual panel—while the other panels remain unaffected. 

While it may seem like a no-brainer to go with the micro-inverter system, there are some use cases where you’ll need to have the classic string inverter system. Your energy consultant will help you determine which system is best for your budget and energy savings objectives. 

Get a free solar installation estimate for your roof.

By entering your address into our solar estimate tool below, you can get an idea of how many solar panels you will need given your energy bill. 


Determining the number of solar panels for your home involves various factors: the size and shape of your home, the quality of panels, your electricity usage, sunlight availability, panel size, and efficiency considerations. By assessing these factors and consulting with an energy expert, you can make an informed decision about the optimal number of panels to meet your energy savings objectives while saving on costs. The best way to gather insights specific to your home is by using a solar estimate tool like the one above.


The number of solar panels needed for an average house depends on factors such as energy consumption, roof size, and sunlight availability. It’s best to start by using a solar estimate tool like the one on this page, then consult with an energy expert to determine the optimal number of panels for your specific needs. 

Solar energy for homes offers a range of advantages, including reduced electricity bills, financial incentives like tax rebates, increased property value, energy independence, and clean renewable energy. 

Yes, it is possible to run a house using only solar energy. However, the feasibility depends on factors such as the size of the solar panel system, energy consumption, storage capacity (if using batteries), sunlight availability, as well as your local utility regulations. A well-designed solar energy system can provide sufficient power for most residential needs. 

The number of solar panels needed for a 2000 sq ft home varies depending on factors like energy usage, location, and panel efficiency. A very rough estimate for an average 2000 sq. ft. home is somewhere in the neighborhood of 40 solar panels give or take. It’s recommended to consult with an energy expert to assess your specific requirements and calculate the optimal number of panels for your home. 

The duration a house can run on solar power alone depends on factors such as the size of the solar panel system, energy consumption, storage capacity (if using batteries), sunlight availability, as well as your local utility regulations. With an appropriately sized solar energy system and efficient energy management, a house can potentially run indefinitely on solar power alone. 

Picture of Jordan Bastian

Jordan Bastian

Jordan Bastian is a highly respected solar industry expert with over two decades of experience. One of the top solar salespeople nationwide, he co-founded Icon Power in 2017 with his brother Jake Bastian. Jordan's visionary leadership and expertise have propelled Icon Power to the forefront of the industry. He is a trusted voice in the renewable energy community, and his blog articles offer valuable insights and practical advice to individuals, businesses, and policymakers. Jordan's passion for sustainability and dedication to driving the adoption of solar energy have made him a trusted figure in the field.

Recent Posts

Press & Media