Last updated on December 4th, 2019
Do you know how much energy a solar panel produce? Here we will explore the production of solar power and the energy a photovoltaic cell can produce.
Solar Power Production: How Much Energy Does a Solar Panel Produce?
When talking about solar power production, we are merely speaking of the energy (in Watts) we get from converting the sunlight into electricity. The conversion can either be done through photovoltaics, indirectly through concentrated solar power or using both methods.
When deciding if you want to buy or lease your solar panels, you should understand how solar panel output works in advance.
The question of how much energy does a solar panel produce is a common one. Many people still cannot say exactly how much energy their solar panels provide.
Although it is always indicated on the panels, and you can always check. It is also essential to understand how to arrive at that amount.
Solar power production is not a distinct element. Rather, it’s a combination of various factors and elements. The resulting energy after the conversion of solar energy by the PV cells is what is referred to as solar panel electricity.
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In this article, we will explore solar power production and help you understand how much energy does each solar panel produce. However, before we get into that, lets first look at factors that affect the amount of energy produced.
Key Factors that Affect How Much Energy a Solar Panel Produces
The amount of energy that single solar panel produce is determined by various factors such as the amount of sunlight, size, and material of the panel.
Understanding how each of these factors affects energy production will help us know exactly how much each solar panel can produce.
Let’s delve in:
The size of the solar panel is the first and the most obvious factor that will influence the amount of energy produced. Its common logic to say that the larger the solar panel, the more sunlight it can absorb and therefore, the higher the amount of energy produced.
If you look closely at a solar panel, you will notice that it is divided by multiple small panels/cells which are joined together by wires. These small cells act as distinct panels in which the conversion electricity takes place.
The cables, on the other hand, act as avenues for transporting that electricity to a junction box.
Therefore, the more the cells in a solar panel, the more power they will create.
This leads us to the conclusion that the larger the panel, the more the amount of solar energy converted holding other factors constant.
See Related: Eco-Worthy Solar Panel Review
Amount of Sunlight
This one goes without saying. The more the amount of sunlight, the more solar energy that will be absorbed by the panels and as a result, more solar energy. To answer the question of how much energy does a solar panel produce, you cannot ignore how the intensity and duration of sunlight will affect production.
Solar panels can absorb the energy from the sun and convert it into electricity. Therefore, if there is no sunlight, solar panels will have nothing to convert.
This is the reason why you should fix solar panels in areas such as rooftops, where they can receive direct sunlight instead of inside the houses.
Although the solar panels can still absorb sunlight energy even when the clouds cover the sun, it is better when they get direct sunlight.
Another critical aspect that affects the amount of energy solar panel produce is a material that is used to make the panel. Different companies make solar panels using various materials, and these materials have different efficiency levels.
The varying efficiency levels of these materials means that some panels may produce more energy than others despite having the same size and under the same amount of sunlight.
There are various material types of solar panels, but two of the most common ones include monocrystalline cell panels and polycrystalline silicon cell panels.
The monocrystalline panels are very efficient although their cost of production is high, making them expensive to acquire.
On the other hand, the polysilicon cell panels, are much cheaper, although they are not as efficient and they also produce more waste.
Having seen the factors affecting the amount of energy produced by a panel, now let us look at the efficiency of the panels.
See Related: Instapark Solar Panel Review
How do We Measure the Efficiency of a Solar Panel?
The efficiency in solar panels means the amount of solar energy converted into electricity, from the energy absorbed from the sunlight. It is crucial to understand that not all the sunlight absorbed, is converted into solar electricity. Even if you buy the best solar panels out there, you still rely on the quality of the sun and irradiance in your area.
Traditionally, the solar panels used to have an efficiency level of between 6% and 10%.
Due to the advancement in technology, the panels have been improved. Now they can reach an efficiency level of even 30% or more.
When measuring the efficiency of a solar panel, you should use a deviancy of + or -2% since the ratings are not 100%.
Calculation of Solar panel efficiency can be as follows:
Efficiency (%) = [Power Rating (watts)/Surface] * 100
Power Rating is the rating (in watts) indicated on the panel and,
Surface stands for the surface area of the panel
For example, if the power rating is 350 watts, and the surface area of the panel is 1800 square meters, then the efficiency will be:
Efficiency = 350/1800* 100 = 19.44%
Here is a video to help you understand capacity factor.
How to Calculate kWh
When calculating the kWh of a solar panel, you need to know the exact number of hours you get direct sunlight and multiply by the power rating of the panel.
For example, if a panel has a power rating of 250 watts, and it gets direct sunlight for 6 hours, you take the 6 hours * 250 watts = 1500 watts. When we convert this, it amounts to 1.5 kWh per day or around 45 kWh per month.
Before you get to calculate the kWh, it is also actually useful to know how to calculate the power rating(kW). Power rating is the exact amount of power any single solar panel produces. So, if you have multiple solar panels, you can establish the total power rating by adding the power ratings of all the solar panels.
It is crucial to understand the power rating of your solar panels to understand how much power you get and how much of your power needs you can meet.
The formula for calculating the power rating is; E=A*r*H*PR, where;
E is the total energy in kW.
A -is the total surface area of all your panels, which you can get by multiplying the length by the width of each panel.
r- is the efficiency rating, which is the same as the one we calculated earlier in the article.
H – is the global radiation value, which is the average quantity of sun-based radiation that is received in a particular area. For example, in Norway, the average amount of sun-based radiation is 200kWh/ square meter per year.
PR – is the performance ratio. This performance ratio is very crucial in determining the exact amount of energy your solar panels are giving you.
How Many kWh can Solar Panels Produce?
Another important question that many people keep on asking and whose answer is essential if you are to understand the amount your panels are giving you. As discussed above, the amount of kWh that a solar panel can produce is dependent on several factors.
The first one is the number of hours the panels receive direct sunlight, and secondly, the power rating of the panels.
For example, if you have three solar panels, each having a power rating of 250 watts, and they receive 5 hours each of direct sunlight, the total kWh will be as follows:
250 watts * 5 hours of direct sunlight * 3 (the number of panels) = 3750 watts per hour, which is equal to 3.75 kWh.
The total amount of energy (in kW) per hour, is always dependent on the number of panels, the rating power of the panels, and the number of hours the panels receive direct sunlight energy.
With that in mind, it becomes easy to know how much is your solar panel production. It will also help you to see if you need extra power to fit your needs or not.
See Related: Best Portable Solar Panels to Buy Today
How Many Solar Panels Do I Need for My Business?
The number of solar panels that you require to fit the power needs of your business will be dependent on varying factors.
First, you will need to know how much power you use per day or month. That is based on the equipment and appliances you have in your business.
Each device requires different amounts of hours. Therefore, you have to add the power needs of all of them to determine how much power you need.
For example, if your business uses an average of 25,000 kWh of electricity per year, it is logical to say that you need around 70 kWh per day (25,000/365 days). The next step is to know how much electricity an average solar panel produces.
For example, the standard panels produce an average of 1- 1.5 kWh per day. If you take 1.5kWh as the average, then you will require at least 47 panels.
The calculations would be like this; [25,000 kWh/365]/ 1.5kWh per day = 47 panels.
Therefore, the larger the business, the more the power needed and hence, more solar panels to cover the electricity needs.
Also, due to varying factors like sunlight and the efficiency of the solar panels, businesses in some areas may require more solar panels than others.
The difference can occur even though both companies need the same amount of power.
How Many Solar Panels Do I Need for My House?
Just like in the above example, the number of solar panels that you require to fit the energy needs of your house depends on multiple factors. Starting from the number of appliances and electronics such as TVs, fridge, lighting and a washing machine that is using the power.
There is no definitive answer to handle this question. The more the appliances, the more the power needed.
In an average home, the number of people living in the house and the number of kWh each use for activities like showering will also significantly affect the power requirements.
In several states, an average household uses around 900 to 1000 kWh on average per month. The power use translates to an average of 30-34kWh per day.
With this estimate, if for example, you have solar panels that produce 1.5 kWh per day, then you require around 22 solar panels to cover for all your power needs.
Again, these are just estimates since multiple factors will affect the production and usage of power.
See Related: Solar ROI Calculator
Conclusion on How Much Energy Does a Solar Panel Produce?
As it’s evident on our above discussion, knowing exactly how much solar panel produce is a tricky question. Although we have given the formula to calculate it, many factors affect the output of your panel.
Therefore, to answer the question of how much energy does a solar panel produce? Make sure that you put in mind all the affecting factors.
Do you use a solar panel at your home? Let us know in the comments below.