Well, you have decided to go solar and have chosen your panels. Now is the time to decide the type of mounting system that will best suit your budget, living space and energy needs. The two types of mounting systems are the ground mount and roof mount racking systems.
The roof mount system attaches to brackets on your roof. But the ground mount systems are built into a foundation at ground level. Both these types have their drawbacks and benefits. Let us have a look at the benefits and drawbacks for each kind and then summarize them. This will prepare you significantly well to decide on the kind of mounting that will suit your needs the best.
Here’s a quick summary of Pros and Cons of Both System
Ground Mount Solar Racking
|• Easy to clean|
• Overall stronger racking
• Cooler panel temperatures mean higher energy output
• Easy to access
• Easier to troubleshoot
• Panels need not be removed at the time of roof replacement
• System not confined to the size of the roof
|• Installation more expensive
• Permitting process more expensive
• Installation more labor-intensive
• Takes up real estate
• Needs more parts and pieces
• Not very aesthetic
Roof Mount Solar Racking
|• Needs fewer materials to install|
• Utilizes unused space
• Less expensive
• Installation labor cost is lower
• Easier to permit
|• Tougher to troubleshoot errors
• Size of the system limited due to space constraint on the roof
• Harder to access, more so, if the roof is slippery or steep
• Higher panel temperature causes less energy output
• Putting holes in the roof could cause water damage
• Difficulty if you need to replace the roof during the lifetime of the panel
Now let’s discuss each in detail…
Ground Mount solar racking has the following benefits :
The solar system will work best only when the solar array can get as much sunlight as possible. It is always tricky to get the perfect alignment in the case of a roof-mounted system. Your roof may not necessarily face direct sunlight. But with ground mount systems, you can face any direction you wish and align the system at the optimal angle so that it receives direct sunlight. Thus ground mount systems maximize access to sunlight.
Beneficial for Grid-Ties and Off-Grid Consumers
The perfect angle and being raised off the ground allow better cooling and airflow thus making the ground-mount arrays more efficient. As a result, more energy is produced.
Maximum solar panels are tested at an average of 77oF. But if it becomes hotter than this, the panels become less efficient and produce 10 -25% less power. This is because semiconductors suffer more resistance to the flow of electricity. But when there are proper airflow and cooling, the panels work in optimal conditions and give proper output.
Giving Room for Growth
If the installation is being made on the roof, the space gets limited. It becomes quite impossible to make the most efficient array. If your energy requirements increase in the future, it would be tough to add more panels.
But if you go ground mount, there is no such restriction provided there is enough space in the yard. The array can be expanded after the initial installation and you can easily make additions.
Solar systems need lots of trial and error, mainly during the installation phase. It will be a headache if you have to move to the roof every time you need to troubleshoot. And if you have considered a system with microinverters and optimizers, then the trouble Is more, as replacing any of these components fitted beneath the panels can be troublesome. You will have to remove many panels to reach the problem. But if the system is at the ground level, troubleshooting is easier.
Also, it is easier to clean and maintain ground mount panels. You will be saved from risk while you wash off pollen and dust, clean off snow or remove debris from beneath the panels. Pole mounts can be considered for heavy snow areas and given perfect tilt to maximize energy production and shed snow during the winter months.
The Drawbacks Of Ground Mounted Solar
- More Upfront Cost and More Labor Intensive
A ground mount is more complex to install and needs more money for completing the work. If you are concerned with maximizing the return of your investment, the roof mount is better-suited.
The upfront cost is more as more parts need to be assembled. In the case of roof arrays, half of the structure is there. But for the ground array, you have to construct a strong roof-like structure so that the panels can be kept in place.
You also need to get your soil surveyed to see if it can hold the system firmly in its place. And you have to dig large holes and pay extra for parts to build a proper foundation for the panels. A lot of these costs can be curtailed with roof-mounted systems, providing your roof is in good shape.
- Takes a Longer Permitting Process
The permitting process is lengthier for the ground-mount system. Moreover, the county or city you reside in may have a heavier hand in the installation process if the system is considered a new structure. You have to obtain a building permit from the authority having jurisdiction in your area. For the same, you will have to –
- Submit a design plan
- Pay permitting fees
- Consider soil nature and property line setback needs
- Occupies Real Estate
This is the main drawback. It occupies a lot of space in your property which you could have utilized otherwise. If you have a huge property, the space issue might not be a big deal. So it may be convenient for people living out in the country. But if your property is small, this is an issue. It might not be an option at all.
Again it might be a bother for people who are aesthetically inclined. For them, it might be like a blemish on their property.
What are the key points to consider if you should go for Ground Mount?
Before going ground-mount, ask yourself the following questions and the answers will take you to the correct decision.
What is the nature of the soil?
If the soil is hard to dig, the installation cost is bound to exceed hugely. And you may have to rent heavy-duty equipment to drill holes in the ground. There are ways to keep digging to a minimum like a ballasted system.
How much do you intend to spend on the upfront cost?
Ground-mount racking needs more labor and parts to install and the permitting process is also lengthier and more costly. But once the installation is done, you will get a more efficient energy output. Also, the cost and hassle of removal of panels are not there if you consider re-roofing. You pay a bit more in the beginning but save over time.
Will there be a need to expand the system?
A rooftop system is fine if you do not intend to live off-grid. Enough energy will be produced for your necessities. But, if, you are planning to go off-grid, the ground mount will give you the scope to add more panels with increasing energy needs over time. Also, you get the perfect tilt so that the panels get the maximum direct sunlight.
What are the benefits of Roof-Mount solar Racking?
The roof-mounting racking system is better for customers who –
- Want a system that is simple to install
- Want to spend less money at the start
- Want to maximize their ROI
- Don’t have a lot of space
The benefits of roof-mount racking :
- Less Upfront Cost
This system needs less time and money upfront for installation. Here the most complex part of the structure is already in place and you need not dig holes or get your soil tested. Further, you need not buy expensive materials like concrete or poles. This racking system is perfect for grid-tied customers who wish to make a smart investment.
- Utilize Unused Space
The roof-mount system is used in houses where there is hardly enough space for a ground-mount system, like if you are living in a tightly-packed suburb or a condo. And the little space you have is best used for the kids to play or for barbecues. When you mount panels on the roof, you are using the space which would otherwise remain unutilized.
This mounting system is also used by people having lots of lands as that is more inconspicuous. Also, the space on your property remains free where you can do farming, raise animals and such other things.
- Increases Insulation and Protection
The roof-mount racking system protects the roof from hazardous elements like UV light, rain, wind, and snow. Also, it provides more insulation. And in case you are living off-grid, this is a cool way to keep your home naturally cooler during daytime and warmer at night.
- Easier Permitting
If you hate bureaucratic processes and their entanglements, the roof-mount racking system is just perfect for you. The permitting process is simpler. You will have to submit the blueprints of your home to show that the roof is structurally sound enough and make sure that the electrical and wiring systems are up to code. It will not be an issue unless you are living in an old home.
You will not have to submit any extra design paperwork as you will not be building a new structure on your property and so no long approval process.
What are the drawbacks of Roof-Mount solar Racking?
The typical downsides of roof-mounted solar systems are –
It would be wise to consider the accessibility factor of your roof. You may not just want to climb on it depending on the pitch and the material the roof is made of. Like, metal roofs are quite slippery. It is also harder to modify and troubleshoot.
- Space Constraint
A part of your roof houses the vents, chimneys and many other obstructions. And you may not have a lot of remaining space to work with. Also if you need to add to the existing structure in the future if there is an added requirement of energy, it will be tough.
- Less Efficient
Roof-mounted systems are usually less efficient as compared to the ground-mount ones as the rooftop panels cannot be aimed at the sun directly. It is difficult to angle an array on an existing structure to optimize for full power consumption during peak hours.
Here you are left at the mercy of the already existing specifications of your roof. You cannot always get the panels to face a particular direction. You may need to buy a few more panels to compensate and match the production of a perfectly aligned ground-mount system.
What are the key points to consider if you should go for Roof Mount?
Get the answers to the following questions before you decide whether you want to go for the roof-mount solar system-
Are there any constraints laid down by your HOA regarding where you can mount your panels?
The homeowners association (HOA) can prevent you from installing solar panels depending on the solar access laws of your state. Check the guidelines with your HOA before making any purchase. Then you can go through negotiations with them while you acquire the permitting order.
What is the age of your roof?
The lifespan of a roof and a solar system is quite the same. So it is always wise to install the solar system at the time the roof is built. Roofs that are less than 5 years of age are ideal for solar installation. If the age of your roof is more, give a thought as to whether you will replace the roof at the time you install the solar panels.
And if your roof is too old, has leaks or damage or issues of structural integrity you may have to think of roof repairs before installation as the roof needs to be in real good shape to withstand the weight of the solar array. Because repairing it after the installation of solar panels will be an enormous task – both physical and economical.
What is the cost of your electricity?
Mostly go solar thinking it to be an investment as it needs a huge financial commitment upfront and the amount of return depends on the amount of energy you consume. The savings will also depend on the state you are living in, whether it is a remote area having expensive electricity.