How Many Solar Panels Do I Need for my San Diego Home?

How many solar panels do I need for a 1,200 sq. ft. house? People often ask us a similar question when they are first introduced to solar energy. However, there is a lot more than just the size of your house or building that needs to be considered when determining the number of panels you will need.

A 1,200 sq. ft. house with two people living in it will likely use a lot less electricity than the exact same house with two adults and two teenage kids. The house with four people will require a bigger system even though the size of the house is the same. That’s why it’s hard to determine the number of panels needed based on just the square footage of a house.

In simple terms, designing a solar system is like putting together a puzzle. It’s difficult to build the final product if you don’t have all the pieces. Below are the pieces you need to get started.

Factors That Will Impact the Number of Solar Panels You Need

Although the square footage of your building will be a piece of the final puzzle, the number of panels you will need is ultimately determined by the following four factors:

  1. The amount of electricity you use
  2. Amount of daily direct sunlight in your area
  3. The amount of usable roof space
  4. The type of solar panel you select

How much electricity do you use? We like to look at your most recent 6 to 12 months of energy usage. Thanks to Net Metering, we can use this history to properly size your system to cover 100% of your yearly usage in most cases.

Put it where the sun shines – The amount of direct sunlight your roof receives will vary based on where you live and the time of year (another reason why Net Metering is a great benefit). Thankfully, we have tools like this U.S. State Solar Resource Map from NREL and extensive local weather station data, as well as other software to help calculate the amount of sunshine in your region.

Not all roofs are created equal – Generally speaking, the perfect roof has a 30° pitch and is facing due south. Since that’s not always realistic, a less than “perfect” roof may need more panels to produce the energy you need. The good news is solar panels are becoming more and more efficient. These improvements have made it more cost-effective to install panels on roofs that face east/west and aren’t the perfect pitch.

Solar panels are not a one size fits all – The efficiency level of solar panels (the ratio of energy produced versus the energy intake from the sun) varies. Efficiency levels have come a long way over the last decade. The panels we install have an efficiency of 16.6% to 21%.

Contact Sunlight Solar, Inc. and get your free preliminary estimate today.
Call us at (858) 564-8032 if you have any questions or you are interested in our services.

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