In 2019, the average single solar panel can produce 300 watts of power.
But is it possible to know how much energy does a solar panel produce?
One way many people answer this is to multiply the wattage of the solar panel by the hours of its sun exposure.
A one square meter panel, for example, with a power output of 150 watts can get exposed to 4 hours of direct sunlight. By simply multiplying 150 by 4 (150×4) this panel would be able to generate 600 watt-hours or 0.6 kWh of power.
Does that mean a 300-watt solar panel can produce 3 kW of energy every hour?
Yes, but under ideal standard condition, which rarely exists.
In order to determine how much energy a solar panel can produce, you must know the three factors that are at play.
Understand how each affects energy output and you can make your energy savings rise with the sun.
1. Size of the Solar Panel
There are two primary sizes of solar panels sold in the market today: 60 cell and 72 cell-panels.
A 60-cell solar panel is typically 65 by 39 inches (5.4 feet tall by about 3.25 feet wide) with a theoretical power output of 300 watts. This is the ideal choice for residential use.
While a 72-cell panel comes in 77 inches by 39 inches, generates 400 watts and given its bulk, it’s more suited for commercial purposes like for utility-scale solar farms.
Which one is more expensive?
The obvious answer is the larger the solar panel array, the more expensive it will be. After all, more solar cells working in tandem means more energy output. That’s why the no. 1 factor that drives up the cost of solar panels is the size.
However, bigger doesn’t mean better energy savings. To optimize the energy output of solar panels means to optimize efficiency which relies on the next factor.
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2. Solar Cell Efficiency
With panel size being equal, some solar panels produce more solar energy than the others.
It all boils down to solar cell efficiency.
A more efficient panel can convert a greater portion of sunlight energy it receives into electricity. If a solar panel is 30% efficient, it can convert 30% out of 100% energy it collects from the sun.
Between size and efficiency, the latter has a greater impact on a solar panel’s energy output.
Because a smaller panel size can meet the desired energy output of a household provided that the arrays of solar cells are more efficient.
We could all desire a solar panel with a 90% efficiency however, that number remains far-fetched. So far, 30% is the highest market standard for solar cell efficiency and although that may seem like a bit low, the passing rate for solar panels is actually anything above 20%.
Amazingly, in the latest line of innovative solar launches, Sunpower recently introduced the world’s first 400-W residential panels with a whopping 60% increase in efficiency. What makes SunPower’s highest powered solar panels ideal for home use?
It can provide longer-term energy in lesser space which proves that bigger isn’t always better.
Could solar panels hit a 100% efficiency rating in the future? No one has even dared to predict this because the third factor that drives energy output in solar panels is an unseen law.
Read More: How Long Do Solar Panels Last?
3. The Quantity and Quality of Sunlight
There are many factors why solar panels can’t absorb a huge chunk of energy from the sun. First, silicon solar cells can’t process most photons it collects from the wide spectrum of the sun.
Scientists refer to this as transmission waste which accounts for about 35% of efficiency loss. Another 15 percent of the sun’s energy gets wasted due to the quirks of the panel’s thermodynamics: seasons change, sunlight moves, solar panels don’t.
Highly efficient technologies have yet to surpass the limits of the sun or the lack of it.
Does it Pay to know How much Energy a Solar Panel can Produce?
The average cost of a single solar panel is $3.05 per watt, whereas the average cost for a residential solar panel system is around $12,810.
Installing solar panels in your home require an upfront investment. A few hundred watts may not leave a huge difference in your monthly electric bill if your household has high energy usage.
But a solar panel with the average energy output of 300 watts should subsidize your energy usage over the course of years.
Whatever your electric consumption, solar panels can provide significant returns for a lifetime, not just on your electric bill but on the planet as well.
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