Solar panels come in a range of weights and sizes. In order to determine whether your rooftop can support a solar panel system, it helps to know how heavy solar panels are.
How Heavy Are Solar Panels?
Solar panels come in slightly different sizes depending on the type, and each one is made up of individual PV cells. These cells come in a standard size of 6” by 6”. The number of cells a solar panel has, relates to its length. The standard size for a residential solar panel is about 65” by 39” (5.4’ by 3.25’), containing 60 cells.
Standard commercial solar panels are a bit larger, being 78” by 39” (6’ by 3.25’), containing 72 cells. The sizes vary depending on the brand. The smaller solar panels are suited for maximizing space on residential rooftops while the larger solar panels are suited for commercial projects. This is because most commercial arrays contain dozens or even hundreds of PV modules.
How Much Do Solar Panels Weigh?
Residential solar panels weigh roughly 40lbs each, however, the weight can range anywhere between 33lbs and 50lbs depending on the manufacturer. Commercial panels weigh in at around 50lbs or more because of their added length. Weight plays a significant role in determining whether or not a rooftop can handle a solar panel installation.
Understanding it is the best way to be certain your roof can support the full installation. Some variation of weight exists among PV brands. For example, one of the top solar panel brands, SunPower, has some panels weighing as little as 33lbs. The brand Canadian Solar has panels weighing as much as 50lbs.
Can Your Roof Support a Solar Panel System?
Knowing the weight load of your solar panel system can help you determine if your roof has adequate structural support. The average solar panel system, including all the hardware components, is about 3-4lbs per square foot. Residential and commercial rooftops are constructed to handle way more than that. They can at least support 20lbs per square foot.
For a 6-kilowatt solar panel installation containing 20 panels, those alone would weigh about 800lbs, having the panels weigh 40lbs each. This system would measure to be at least 352 square feet, calculating at a weight of 2.3lbs per square foot. More worn-down roofs and ones to have suffered previous damage might not contain the necessary structural support for solar panels.
A professional PV contractor can usually determine whether a rooftop has the capability to support PV panels. However, these professionals are not necessarily roofing experts, and can’t guarantee a roof is structurally sound. It’s best to contact a professional roofing company if you have any concerns about the integrity of your roof.
Can You Walk on Solar Panels?
It’s crucial that you do not walk on your solar panels! The solar cells can easily break. Based on NREL research, silicon solar cells will crack if you walk or kneel on them. However, the damage isn’t at all visible when the cells are packaged in the module.
Once it’s cracked, over time, the effect on the power output of the solar panel will get worse. The changes in temperature correlated with day and night cause contractions and thermal expansions which help pull the materials surrounding the crack apart.
Do Solar Panels Last Forever?
The longevity of solar panels is a common concern of most homeowners. Not knowing how long solar panels last make it difficult to understand the upfront cost of solar panels. They’ll have the ability to offset the use of your electricity for decades, and will last for about 25-30 years. This doesn’t quite mean that your solar panels will stop producing electricity after 25 years.
This means that the energy produced will significantly decline. Since there’s no physical damage by any debris, wind or any other external factors, they’ll continue to work for many decades. This mainly has to do with the fact that solar panels do not have any moving parts whatsoever. They hardly ever break from within and are often only damaged by forces from outside, such as extreme weather conditions or poor racking setup.
How Many Solar Panels Do I Need to Run a Freezer?
The average, well-structured solar panel will generate about 30 kWh within a typical month, while an average fridge uses around 57 kWh. A freezer uses about 58 kWh every 30 days, being a total of 115 kWh. With that being said, dividing the two will get you an average of 3.83 solar panels.
How Many Solar Panels Are Needed to Run a House?
A standard U.S. home uses approximately 10,400 kWh of electricity each year. Installing an average 250-watt solar panel requires about 28-34 solar panels to generate an adequate amount of energy to power an entire home.
Also Read: How to Calculate Solar Panel Power Output
For more information, visit our website or contact us today.