solar panel

What is the Sun Number Score?

A Sun Number Score is a rating between zero and 100 that represents your home’s solar power potential. With zero being the lowest and 100 the highest, the higher your Sun Number Score is, the better suited your home is for generating solar energy.

Sun Number Scores are important because they represent the viability of adding solar panels to a building — essential information for both existing homeowners considering solar energy, and people looking to buy a home and install solar panels. While square footage, yards and decks, multiple stories, and more are factors that many consider when searching for a home to purchase, Sun Number Scores are becoming increasingly requested. Higher Sun Number Scores also represent greater potential savings in electricity as well as increased property value if homeowners plan to sell or rent their residence in the future. 

What is a good sun number score?

While the Sun Number Score scale ranges from zero to 100, a score of 70 or higher is considered a great score. If your score is 70 or above, adding solar panels to your home is a wise decision, with almost guaranteed financial savings in the long run. While rare, a score of 100 means your home is perfect for solar panels. It really can’t get any better. 

Almost no homes will qualify for a perfect Sun Number Score, but that doesn’t mean solar panels aren’t the right choice for your home. Even if your score is below 70, you may still be able to benefit from a solar panel system, albeit with a lower energy output.                       

flexible solar panel

Additionally, if your Sun Number Score is lower than average, your system might just require a more complex solar panel design to absorb as much sunlight as possible. On the other hand, an above-average Sun Number Score doesn’t necessarily mean that you need to install solar panels. But it’s a great feature to take note of if you plan to sell your house in the future — homes with higher Sun Number Scores typically have higher property values since solar panel systems are usually installed.  

Factors that influence your sun number score

Building score

Roof slope, orientation, and size determine your home’s building score. It’s best to have a building score no lower than 50, and above 60 is considered a great score for the solar power potential of your home.The more area your roof has to support and install solar panels, the better, and the direction your roof faces is important, too. South-facing roofs will see the most sunlight and generate more than enough solar energy to power their home. There’s higher potential for excess energy production, too, which can be stored in a battery as backup power, or even sent back to your city’s grid to redeem credits. Roof slope is also important. Solar panels function best when positioned at a 30-degree angle. If your roof slope is less or more than this, tilt brackets can tweak your pitch based on the steepness and positioning of your roof.

Regional climate score

The area surrounding your home plays a role in your Sun Number Score as well. If your residence is in a shaded area with numerous trees, buildings, or other obstructions blocking the sun, this can lower your score. Climate and weather conditions can affect your Sun Number Score, too. Does your region have a higher number of sunny days than others? Colorado, for example, experiences around 300 sunny days per year, making it an ideal location for high solar power potential. Areas that experience numerous overcast days, on the other hand, aren’t doing your score any favors. To calculate the regional climate score for your house, Sun Number relies on solar irradiance data from the National Renewable Energy Laboratory (NREL).            

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Electricity score

Sun Number considers the average electricity rates in your area to determine how beneficial solar panels are for your home. Since solar panels will save you money on electricity over a lifetime, the higher the electricity rates in your area, the higher your Sun Number Score. In areas that have lower electricity rates, you won’t see much or any increase on your score. 

Solar cost score

Local costs for solar installations have an inverse effect on your Sun Number Score compared to local electricity rates. The lower the cost is to install solar panels in your area, the more points you’ll gain on your score; and higher installation costs will do the opposite. 

Whether your Sun Number Score is on the low or high end, you’ll likely benefit from speaking with a professional to weigh your options for acquiring solar panels for your home or business.For more information on purchasing and installing a solar panel system, or to discover your home’s solar power potential, contact SOLARPARTS.

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