How Many Solar Panels Do You Need?
Hint: You need to carefully consider the size of the solar panels and the Output Contributors.
To know the number of solar panels that you can apply in your own home requires identifying your goals.
If you are inclined to saving the world by minimizing your carbon footprint, you will have to rethink the quantity options, and this also applies if you are maximizing your investment.
But all of this is still all up to you.
To help you decide, here’s a formula to identify the solar panel requirement in your household: the amount of household energy consumption, the surface area of your roof, the weather conditions and light intake in your area, the efficacy and wattage of the solar panels per photovoltaic (PV) cells, and the availability of net metering.
If you are in a hurry and would want to install immediately, here’s a simple answer to your question: consult a professional solar panel installer.
Most of them offer a free evaluation of your household’s solar exposure and accessibility.
Frequently Asked Questions on Solar Panel Installation
What is the total watt consumption of your household?
A simple way to know this is to be mindful of your electricity bills.
To check your average usage, you can try looking for ‘kilowatt-hours used’ in the bill papers and jot down the period that it ran, which frequently amounts to 30 days.
If no label pertains to this, you can consider subtracting the previous reading from the ending meter readings.
It will also give you the hindsight of electricity consumption.
It is necessary to have sufficient knowledge of your hourly and daily usage to know this.
To obtain the average daily reading, you can divide the monthly average by 30 or the annual average by 365 days.
Then, divide it again by 24 to know the hourly average.
Kilowatt-hours is the unit of measurement used in expressing electric consumption.
It is the standard measurement of power usage multiplied by the total time covered usage.
For tiny houses located in temperate zones, the approximate usage is about 200 kWh per month.
But it’s different for Southern areas where the average consumption is more significant.
Large households that utilize air conditioners use 2,000 kWh in a month or even past exceeding such threshold.
In the U.S., their homes garnered an average of 900 kWh per month.
If we are to break it on a day-to-day basis, it means that they spend 30 kWh each day or an hourly usage of 1.25 kWh.
The daily consumption of energy must be the target you need to know to prospect your solar needs.
It must cover the 100 percent energy requirement you need before installing the solar system panels.
You should also put in mind that solar panels are not working at maximum efficiency.
It is due to its reliance on weather conditions which might reduce the efficiency.
Hence, if you have solar panels, you must add a 25 percent “cushion” of your energy target to ensure that the energy obtained is sufficient.
What are the contributors when talking about the efficacy of your panel output?
Like all products, solar panels have their differences.
Photovoltaic (PV) solar panels are a necessary component to consider.
It usually ranges from 150-370 watts to each panel, and it will still be dependent on its size and “efficiency” or its ability to convert sunlight to usable energy.
Some solar cells have no grid lines.
It is advantageous because these are proven to absorb sunlight effectively and are resistant to common panel problems like peeling or delamination.
They are also well-constructed that their cells are more robust and could withstand corrosion or shock.
It is also necessary to figure out if there is an existing microinverter to optimize conversion.
The variations make it very difficult to find the exact solar panels that will fit your preference.
Quality and efficiency are the factors you must consider finding the right ones.
But here’s a takeaway, efficient panels are the ones to produce more watts, and it means lesser panels to install in your roof to provide the needed energy.
The most common production of solar panels is around 250 watts for each panel, but the efficiency levels vary.
Meanwhile, the most renowned panels in terms of efficiency are the SunPower panels.
Here’s an image of the amount of solar panel power usage. In Dallas, Texas, a household can use 25 conventional panels with 250 watts capacity, but only 17 SunPower may exceed this as it holds a total of 370 watts.
How does the solar panel size affect the conversion efficiency?
It is an important consideration to note, especially if you have a small or unique roof the size of the solar panel.
For a rooftop with a broad and usable area, you may choose larger panels and trade them for efficiency to save money, and you would still have an energy output that befits what you need.
But, it is a different situation if you have a small, partially shaded roof. You would need a smaller panel with higher efficiency, and you need to choose well to appropriate your money accordingly.
You have to consider the average dimension of solar panels that we have today in the market. Usually, panels are around 65 inches x 39 inches or 5.4 feet x 3.25 feet which varies slightly among manufacturing companies.
These dimensions have changed over time as manufacturers alter the efficiency and output that the solar panels may incur.
They also changed the appearance, including the virtual lack of gaps among the panels and the transparency of frames to make it efficient and attractive for consumers.
For sure, you now have an idea in mind on what is the ideal number of the panel that you should buy to hit the electric consumption target that your household needs.
You can now check for a potential installer to professionally check your roof’s characteristics, as well as its angle of exposure from the sun, to determine the proper arrangement of your solar panels.
A strategized installment will help you reach your energy production goals.
But before you start, there’s one more tip to be considered, which is net metering.
It is essential in solar panel systems to allow utility companies to credit you for the excess electricity that your panels generated during the daytime and use this credit as a power source at night.
You will surely appreciate this tip if you still can’t afford battery storage for solar energy.
How much is your target total solar energy?
We kept on repeating the term target total solar energy, but how do we compute it?
The formula for this is simple, and you can immediately do this by looking past your utility bills. You can determine the number of solar panels through this simple math.
First, multiply your home’s power consumption and the direct sunlight peaks in your location, then divide it with the wattage of your panels.
Also, you can establish the range by following this, 150 Watts for the low-wattage while 370 Watts for the high-wattage.
It will help you approximate the energy requirement of your household and the sunlight exposure of your roof.
It will also consider the factors like your roof’s shape and size and the battery storage.
Some companies are also offering to do these calculations, and it would be helpful to ask the professionals for a thorough insight.
What should you expect in your area in terms of hourly sunlight exposure?
In a regular US household with five peak sunlight hours in a day and an average Kilo-watt usage of 900 kilowatts per month, the solar panels must produce 6,000 watts. It is very crucial to be aware of this.
The peak sunlight hours will determine the duration of total exposure to the sun in a day.
To have a sufficient understanding of the average sunlight exposure per day, you also have to know how this impacts the number of solar panels that you might use.
To live in Phoenix will give you more sunlight hours than in Seattle, and you need to be wise enough to use this location advantage in your favor.
We’re lucky to have the Renewable Resource Data Center that offers data on sunlight exposure in different states and major cities.
You can use this to create an approximation by multiplying your household’s power usage on an hourly basis by 1,000.
It will convert the result to watts, and this will be your average hourly wattage consumption.
Finally, divide this with the daily peak sunlight our of your location.
The result is the exact amount of solar energy that your panels must convert per hour.
If you are still unsure about shifting to solar energy, you have to make up your mind.
A quick internet search on solar calculators will immediately give you an idea of the solar energy output that you will save and consume in the future!