How much energy does a 300-watt solar panel produce?

Francisco CastroApril 30, 201980730

How Much Energy Does a 300-Watt Solar Panel Produce

Solar panels come in a variety of wattage sizes, but currently, most range from 250 to 400 watts. 

Your average amount of energy consumption per year and the standard solar panel wattage will determine how many you need to be placed on your roof.

Trying to figure out the solar panel you need can be a daunting task. But we’ll try to explain it.

Solar cells

Most standard solar panels contain 60 square photovoltaic (PV) cells; there are also 72-solar cell modules, which are a foot taller and are mostly used for commercial projects.

The PV effect was discovered in 1954 when scientists at Bell Telephone discovered that silicon (an element found in sand) created an electric charge when exposed to sunlight.

Solar cells are often less than the thickness of four human hairs. In order to withstand the outdoors for many years, cells are sandwiched between protective materials in a combination of glass and/or plastics to make a PV module.

An individual PV cell is usually small, typically producing about 1 or 2 watts of power. To boost the power output of PV cells, they are connected together in chains to form larger units known as modules or panels. Modules can be used individually, or several can be connected to form arrays. 

No matter how large your array is, all the solar panels will be linked together by wires, which carry the electricity from the cells to an inverter. The more cells and the more panels working together, the more energy they produce.

So how much power can you get from a 300-watt solar panel?

Each solar panel comes with a label detailing its maximum electricity output, which is measured in watts. Wattages are assigned according to each panel’s peak capacity for generating energy during optimal circumstances in laboratories, also known as STC (Standard Test Conditions). But in the real world, you can expect a drop in performance, or what is referred to as PTC. 

The output will be determined by the amount of sunlight the panel receives and your location. But the energy output is not often steady throughout the day or even during sunshine hours. They will produce less in the mornings or late afternoon (when the sun is low in the sky) compared to mid-afternoon, when the sunshine is directly falling on them. 

Also shade of any type - even passing clouds - covering only part or the entire module, can reduce the amount of electricity generated by a panel.

In addition, solar panels will generate more power during the summer and spring, than winter and fall, simply because of the change of the position of the sun.

All of this means that a 300-watt panel may produce as little as 100 watts in the early morning and late afternoon and any other amount as the sun traverses the sky in the day.

When a solar installer places the solar panels on your roof, he will try to adjust them in a position and angle that takes advantage of the maximum amount of sun hours for that particular area. 

You can consult the National Renewable Energy Laboratories (NREL) to find out the number of sun peak hours in your area and other data.

For instance, the average solar radiation for Los Angeles is 5.84.

To find out how much power a 300-watt panel produces, you would multiply 5.84 x 0.3 = 1.752 kWh per day

To get the total amount of electricity generated by a solar array, you would multiply that figure above by the number of panels.  

How many 300-watt panels do you need for a 5kW system?

Now, if you want to find out how many of those panels are needed to power a 5kW system on your roof, you would divide 5,000/ 300 = 16.6 (17)

300-watt solar panels are relatively efficient with the space they use when compared to lower wattage panels, and a standard roof of a single-family home will likely have enough space to accommodate the right number of them to offset the electricity used by the household. 

If you want to make the switch to solar power and want to know how much it will cost for your energy needs, you can do it very fast and easily. The Hahasmart price checker gives you this information in a matter of seconds by simply using your address and average monthly utility bill. They’ll recommend what the correct solar power system is for your home to offset those electricity costs, the total cost of equipment and even an estimated cost of installation of your solar panels.

Efficiency Rating

Something else to keep in mind when selecting a solar panel is efficiency rating, another measurement that will be detailed in the module’s label.

An efficiency rating measures the percentage of sunlight hitting the solar cell that gets converted into usable electricity. The greater the efficiency, the less surface area it will take for the solar panels to meet your energy requirements—but the higher the price tag.

Most solar panels are between 15% and 20% efficient. Higher quality modules may even exceed that. 

If one panel has an efficiency rating of 20% and the other of 15%, the first one will produce 33.3% more kilowatt hours (kWh) than the second one under the same conditions. 

For more information, click below;

HahaSmart Blog - More Solar Tips and Guide
HahaSmart News - Stay Informed
Your Solar Incentives - See Credits and Incentives in Your Area
Check Your Home's Solar Price - See How Much You Save
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