Before installing panels, you must determine the appropriate number of solar panels to install

One of the most common problems faced by homeowners is deciding the right number of solar panels to install. Selecting and installing the correct number helps homeowners generate the required amount of electricity without spending extra money.

While most solar panel installation companies use a ballpark figure to estimate the number of panels, some generalize it based on the number of rooms that will be connected to the solar power system for electricity. In this article, we will help you to calculate the right number of solar panels to install.

Calculate Annual Kilowatt Hours (kWh) Usage

  • The first step is to calculate your annual kWh usage, as this will help you calculate the right number of solar panels to install. Sometimes people install old panels which are cheaper than newer ones. However, you must take care as most old panels might suffer from irreparable defects that would render them useless. The only solution for a faulty solar panel is to hire a solar recycling company to recycle it.

You can gather your electricity bills for the last six months, and calculate the sum of your usage. If your area has exceptionally cold winters or hot summers, you will need to increase your sample size. You can look at your electricity bills for the past year, or ask your energy company to provide you with a summary of your usage for the past couple of years.

  • A kilowatt hour is a unit used to measure energy. If there is an appliance that is rated for 1kWh, it means it will consume 1kWh of energy in one hour. The amount of kWh used per month is calculated and billed to you by your electricity company.

Once you have your annual kWh usage, divide it by 365 (if for one year) and you will have your Daily Usage (kWh).

Calculate Minimum Solar Array Output

  • The minimum solar array output helps you to get an idea of the minimum energy size of your solar system that needs to be installed. It is always a good idea to install a solar system that is slightly larger than this system. The following calculation will help you calculate it.

Daily Usage (kWh) / Sun Hours/ 0.9 inefficiency factor = Minimum Solar Array Output

The Sun Hours refers to the number of sun-light hours at your location each day. It varies from location to location. If the number of hours varies each season, you can take an average to make calculations easy.

  • The inefficiency factor is used to take into consideration, the variety of factors that can affect your solar system to operate below its optimum level. This factor can be reduced by increasing your home’s energy efficiency.

Calculate The Number of Solar Panels Required

  • The minimum solar array output is in kW. To convert it into a watt simply multiply the value by 1000. The amount of energy generated by solar panels is usually denoted in watts. So to calculate the number of solar panels required divide the minimum solar array output by the power of the solar panel.

For example; Let’s assume your minimum solar array output is 5.95kW. After converting it to watts, it becomes 5950 watts. If you are considering installing 335W panels, simply divide 5950 by 335, and the result is 17.7 panels ~ 18 panels. You must take precautions, as this is only a rough estimate, and your actual needs might be higher.

Additional Considerations

  • number of solar panels to installWhether you are installing a grid-tied system or an off-grid system, you must make sure you protect your solar panels from damage and take good care of their maintenance. Solar panels that are damaged or not properly maintained generate less electricity than they are supposed to.

If you are installing an off-grid system, you must weigh the pros and cons of the different types of backup batteries and install the one most suitable to your circumstances.

If you have faulty or damaged solar panels that can no longer be repaired, why not play your part and hire a solar recycling company to recycle them? At PV2 Recycle, we take pride in being one of the best solar panel recycling companies. Contact us today at and learn more about solar panel recycling.

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