Ground Mount vs Roof Mount Solar Systems: A Comparison
There are a couple of different types of installation methods for solar panels. Here at Paradise Energy Solutions, we install roof-mounted solar panels, ground-mounted solar panels, and carports. These installation types accomplish different goals, and what works for one customer may not be the best option for other customers.
It is important to examine the advantages and disadvantages of all installation types when considering solar for your business, farm, or home. The goal of this blog post is to highlight the things you need to know to make an informed solar investment decision.
Before diving into the list, let’s first define what a ground mount and roof mount solar system is.
A roof mount is the most common type of installation. This is when the solar racking, which holds the panels in place, is installed directly on the roof. Panels can be attached to flat or sloping roofs consisting of metal, shingle, or rubber materials.
Not all roof-mounted systems require penetration to be secured to the roof. If you have a flat room, a ballast mount is an option. These installations are secured by blocks that weigh the system components down.
A ground mount is when the panels are secured to a rack structure that is connected to the ground with steel beams or another type of metal post. Ground mounts can be installed in an open area or as a carport over a parking lot.
Ground mounts can be installed wherever the conditions are best for solar, making them a great alternative for someone who doesn’t have enough usable roof space or just prefer to not have panels mounted to the roof.
Pros of a roof mount:
Roof mounts utilize space that otherwise wouldn’t be used.
Typically the installation cost is lower compared to a ground-mounted system
Doesn’t take up land that could be utilized for other activities
Limits unauthorized visitors from accessing the panels
Panels can protect the roof from exposure to certain elements
Cons of a roof mount:
Roof penetration is required for shingle roofs
Could require a new roof before installation
You might have to remove and reinstall panels for roof repairs or to install a new roof
Adds weight to your roof, and in some cases, the roof could require additional support mechanisms
Some believe solar hurts curb appeal
Can be a safety hazard for the installation team
Things to consider when installing a roof mount:
The age and condition of your roof
The impact solar could potentially have on your roof warranty
Ground-Mounted Solar Panels: What You Need to Know Before Investing
As its name suggests, a ground-mounted solar system is a free-standing solar array mounted on the ground using either a rigid metal frame or atop a single pole. Ground-mounted systems can take the place of a rooftop system when the latter isn't available or suitable. Both provide greater benefits than relying on fossil fuels for your electricity needs. Not every roof is suited for solar panels. but not every home has the extra space needed for ground-mounted panels.
Depending on your space requirements, ground-mounted solar panels can be a more worthwhile investment than rooftop panels. The list of benefits is longer than the list of drawbacks, but every individual situation is different.
Your roof may not have the structural integrity capable of supporting solar panels. A professional contractor or inspector can determine its suitability.
Asphalt roofs also need replacing roughly every 10 to 15 years. You may also not like the aesthetics of solar panels on your roof, or perhaps your homeowner's association prohibits rooftop installations.
If you have a big enough lot, you can set ground-mounted solar panels beyond the sight from your house or immediate yard. If you are lucky enough to have a second property or are able to lease land somewhere, you can install ground-mounted solar panels on that property, then get credit through a net metering program for the electricity that they send into the electrical grid. (This is how community solar programs work.)
While a roof that faces north-south can still support solar panels that generate electricity, the amount of solar radiation they receive may make the panels not efficient enough to pay for themselves. Ground-mounted systems can be placed without obstructions like chimneys, trees, or neighboring structures, shortening the payback time.
More easily than rooftop panels, ground-mounted ones can be adjusted according to the season or can support a solar tracker that follows the path of the sun throughout the day. A ground-mounted system with a tracker can be 10% to 45% more efficient than a rooftop solar system.1
The larger height of ground-mounted panels means they are better suited for bifacial panels, which have solar cells on the back of the panels that capture light reflected off the ground or other hard surface. Because air flows more freely around ground-mounted solar panels than rooftop panels, they are less likely to suffer from heat buildup, which reduces the efficiency of solar panels.
Types of solar mounts
There are many types of solar mounts, but the three primary options for commercial solar arrays include rooftop, ground mount, and parking canopy locations.
Empty rooftop space is a great location to place solar panels and is often abundant in large commercial buildings and distribution centers. When evaluating for rooftop solar, it’s important to consider the age of the existing roof, geographical latitude, weather conditions, roof slope, and shading from adjacent buildings or vegetation. Melink uses a ballasted roof mount racking system, meaning that we typically do not make roof penetrations.
For commercial solar PV systems, there are generally three types of roof mounting options and the solution is dependent on the type of roof. In all cases, considerations must be made for the roof’s age, structural integrity, access to equipment, and necessary setbacks for fire and life safety requirements.
Roofs that are flat with a slope less than 7 degrees are commonly able to utilize a ballasted racking system. This ballasted roof mount system does not generally require roof penetrations and will add roughly 3-7 PSF of weight to the roof. In areas where the roof cannot structurally support this added weight, mechanical attachments can be used. With this type of system, the solar modules are typically installed with a pitch of 5, 10, and 15 degrees.
Installing solar on a standing seam roof typically results in the lowest installed cost per watt, as the racking system for a standing seam roof is the least expensive. The racking systems typically used for standing seam roofs do not penetrate the roof but rather use a special clamp that secures the solar array by attaching to the roof seam. Solar panels can either be mounted flush with the slope of the roof or installed at a higher pitch. The higher pitch increases production but can also increase cost and will require spacing between rows.
Installing solar on a pitched shingle roof generally requires the use of special flashing attachments to mechanically attach the solar array to the roof structure under the shingles. It is most common for solar modules to be mounted flush with the slope of the existing shingle roof.
The different types of solar panel mounting systems
Solar Panel mounting refers to methods of which solar panels are secured into place. Whether you are looking for a solution for a pitched roof, flat roof or field there is a unique mounting system at hand. Different kinds of solar panel mounting allow for design flexibility, varied aesthetics, and greater solar generation. Here at Deege Solar we have years of experience installing various different Solar PV systems. Every project is unique, meaning that not one type of Solar Panel mounting system suits every solar project. In this blog we will explore the different kinds of solar panel mounting systems available, hopefully helping you find the perfect Solar mounting system for your solar project. By far the most common kind of solar panel mounting is an on-roof system. As the name suggests, the solar panels fix directly to the roof. On-roof solar panels, are a cost-effective solution. Providing excellent ventilation to your panels and optimal performance. When installing an on-roof solar system, metal hooks are drilled directly into the rafters of the roof. This involves sometimes removing and replacing some roof tiles. Vertical rails run across the hooks, to which your Solar PV panels are clamped onto. Finally, a weather proof seal is applied around the hooks for maximum protection.
In roof solar, or integrated solar panels are the ideal solution for new builds or anyone looking to re-roof there home. Many customers opt for an in-roof system because of the sleeker aesthetics. As the solar panel sit snugs within a tray, there is no space for birds to nest under and the panels appear flush with the rest of the roof. However, this does result in less air ventilation around the panels, resulting in a 5-10% lower efficiency.
Solar Mounting Structures: Racking Matters
Globally, solar installations have been growing at an impressive pace. A large share of growth has been contributed from India, and with 100GW of target by 2022 in its hand, India is on the verge of becoming the world’s biggest solar nation. Continuous reduction in the solar system prices with respect to higher grid rates is resulting in increasing global demand for solar solutions and thus leading to its rapid growth. Solar is undeniable the future and a leading source of renewable energy. Solar panels work best when they receive shade free sunlight for maximum number of hours, mounted at precise tilt angle with face directed towards the south. This is where Solar Panel Mounting Structures comes into the picture. One of the largest areas of innovation within solar panel installation involves the mounting system.
Module Mounting Structures play a vital role in efficient working of a solar power system, both in utility and rooftop. While most of the components of balance of system (BOS) such as inverter, DC cables, junction boxes, transformers, etc. are readily bought from the equipment suppliers, the workmanship of an EPC contractor is reflected mainly through module mounting structures and wiring management.
