How Many Solar Panels Do I Need For My Home?


Making the switch to solar energy is a big decision, but it can be an incredibly rewarding one. Figuring out how many solar panels you need to power your home can seem like a daunting task, but it doesn’t have to be. In this blog post, we will break down everything you need to know about sizing your solar system and finding the right solution for your needs.

So, whether you’re just starting to explore solar or you’re ready to make the switch, keep reading for all the information you need!

How Many Solar Panels Do You Need To Power A House?

It’s vital to consider a variety of factors when figuring out how many solar panels are required to power a home, including the weather where you live, the panel’s wattage capacity, and the typical electricity usage of your individual household.

To determine how many solar panels you need, use the table below:

The quantity of panels you require depends on a number of factors, including use, wattage, and weather.

Electricity Consumption

Look back at your entire energy usage from the last 12 months on your utility bills to better understand your personal usage. A typical electric bill will list the total number of kilowatt-hours (kWh) of electricity you used in that particular month and then charge you for each kWh. As a point of reference, the average price of electricity in the United States in June 2022 was 15.42 cents/kWh.

Because usage changes with the season and other variables, you can calculate your annual electricity needs by adding the kilowatt hours used over the course of the previous 12 months. As stated by the U.S. According to the Energy Information Administration (EIA), 10,715 kWh of power was used on average year in 2020.

Wattage

The differences between the three primary types of solar panels—monocrystalline, polycrystalline, and thin-film—are more completely covered here. All differ in their cost and level of effectiveness. The amount of power the solar panels can produce will determine how much you’ll need to power your home.

The estimated power output of a solar panel is indicated by its wattage rating under optimum weather and sunlight conditions. The majority of panels in 2022 had wattage ranging from 250 to 400, with larger wattages being preferred but nearly invariably more expensive.

The system power is the product of multiplying this wattage rating by the quantity of panels. Every residence has a varied exposure to the sun’s zenith, and this must be taken into account when calculating the system’s overall wattage.

System power, which is expressed in watts, differs from the quantity of energy the house would use, expressed in kilowatt (kW) hours. A 5 kW system will never change from being 5 kW. But depending on a variety of external conditions, chief among them how much peak sunshine the panels receive, it might produce more or less power. Therefore, the same system can be enough for a residence that consumes 14,000 kWh in one state but only 10,000 kWh in another.

Weather Condition

Since solar panels don’t work continuously, the weather and the seasons have a significant impact on how effectively they generate solar energy. The amount of sunlight and the season affect how much power a solar system produces. A residence in California will receive significantly more sunlight throughout the year and generate more kilowatt hours of power than a similar-sized house in Michigan if both have a 5 kW solar array.

The production ratio is the ratio of the system’s estimated energy output over time, expressed in kilowatt-hours, to its actual size, expressed in kilowatts. As an illustration, the production ratio of a 10 kW system that generates 14 kWh of electricity in a year is 1.4 (14/10-1.4).

The production ratio ranges from 1.3 to 1.6 in most U.S. regions. In the example given, the Michigan house has a lower productivity ratio than the California residence. This does not imply that the Michigan home’s solar system cannot provide all the necessary power. It simply implies that in order to produce the same amount of solar power as the California home with 5,000 watts, it need additional solar panels and a larger system, possibly closer to 6,000 watts.

The production ratio for a solar panel array in your unique region can be determined using data that is specific to your solar installer.

How to Determine the Number of Solar Panels You’ll Need

We’ll need three pieces of information to determine the size of your entire system: the amount of sunlight you receive, your typical energy needs, and the wattage of the solar panels you utilize.

Analyze the Amount of Sunlight You Receive in Your Area

You must determine how many peak sun hours you may expect to receive in a day where you now reside. Because some days are sunnier than others and because summertime sun exposure is longer and more direct than wintertime, this value represents an average day.

Depending on where you reside, you will enjoy a wide range of peak sun hours. Homes in sunny southern California receive significantly more sun exposure than those in cloudier northern Michigan. Additionally, the time of day matters because the intensity of the sun varies depending on whether it is 9 a.m. or not. or 12 p.m. or 4 p.m. — just like the angle at which sunlight strikes a solar panel.

Find the number of peak sun hours you receive each month to start calculating how many solar panels you’ll need. Simply multiply your peak solar hours (for instance, 4.6 hours) by 30 (the typical number of days in a month) to get the following result: 4.6 X 30 equals 138 solar hours.

A peak solar hour technically occurs when sunshine exerts 1,000 watts of energy per square meter. It sounds difficult to understand, but thankfully science has already done the challenging study so you don’t have to. For any region of the United States, researchers have identified the peak sunlight hours, and the information is easily accessible. 3 to 6 peak sun hours are received daily in most of the U.S.

Calculate Your Average Energy Needs

The projected annual kilowatt hours required are then divided by the number of months to establish how many kilowatts of power our system requires each month. Your electric company can provide you with information on your usage, but for this example, we’ll use 10,715 kWh, the national average: 12,015 kWh/10,715 kWh = 893 kWh

We divide the monthly kilowatt hours required by the amount of peak solar hours we receive in a month to calculate how many watts our system requires: 138 hours/893 kWh equals 6.47 kW

We are now moving forward. We have found that we require a 6.47-kilowatt solar system to satisfy our energy requirements. System size is another name for this figure. We first convert 6.47 kW to watts to determine the number of panels we will require to construct a system that size: 6.47 x 1,000 = 6,470 W

Determine How Many Solar Panels You Need by Picking One

Consider selecting a 340 Watt high-efficiency monocrystalline pane. Although this panel will cost extra, it has a lot of power. Here is how to calculate how many you require. Divide the system’s overall wattage by the wattage of a single solar panel as follows: 6,470 W / 340 W = 19.02

Therefore, for this particular property, 19 solar panels with 340 watts of power should be plenty. Professionals frequently advise rounding up, and in reality, the majority of American households need between 20 and 30 solar panels to supply all of their electrical needs.

Conclusion

The amount of solar panels you need for your home depends on a variety of factors such as the size of your house, the direction it faces, and how much sunlight it receives. 

A typical home requires about 30 solar panels to provide enough power for all its needs. You can always install more, or fewer solar panels based on your specific needs. 

If you’re interested in learning more about how many solar panels you need for your home, check out this guide and start saving money.