Early in your solar planning process, you’ll probably ask all sorts of questions to determine what type of commercial solar design would be best for your organization. Is commercial rooftop solar smarter than a ground-mounted solar system? What about solar carports? When does one kind of onsite solar installation make more sense than another?
If you’re asking good questions like these, you certainly aren’t alone. In fact, any organization seriously considering a commercial solar energy system must take a close look at its property and facilities—not to mention the public statement it wants to make—when deciding which solar configuration is best for the long term.
So let’s dive a little deeper into the three major (and most popular) types of onsite installations and what you should know about each.
Taking it from the top: commercial rooftop solar
Roof-mounted solar panels are probably the commercial solar design you’re most familiar with, and for good reason. They’re most often chosen by commercial organizations, and they're usually the quickest and easiest to set up when plenty of open, sunny roof-space is available.
Depending on your roof, commercial solar energy systems can be attached, ballasted or some combination of both. “Attached” means they’re physically secured to your roof, while “ballasted” means they rely on the weight of the installed system to stay in place.
The three most important considerations for commercial rooftop solar are:
- Does your roof get enough bright sunlight?
- Is your roof strong enough?
- Is your roof optimally configured for solar panels?
As you work with your solar provider, they’ll conduct tests to determine whether your roof really is the best place for your panels. Sometimes a roof—because of rooftop obstructions like HVAC units—won’t be able to support large blocks of solar or may simply be too old to be cost-effective.
If rooftop solar is feasible, panels installed on your roof can provide extra insulation for your building, making it cheaper to cool in the summer. Plus, they can protect your roof from harmful UV light. If you’re planning to install a new roof in the near future, it’s a great time to consider adding rooftop solar so that it can be mounted after the new roof has been installed.
Power from the ground up: ground-mounted solar systems
If your roof can’t handle or accommodate a commercial solar energy system large enough to generate the energy your organization needs, ground-mounted solar offers another smart option. In fact, as long as you have the land available, a ground-mounted installation can be just as easy to build, operate and maintain—plus it can help you make the most of unused space.
As you can probably guess, ground-mounted systems are essentially racks, anchored to the ground, that support a large number of solar panels. Typically, these solar panel racks are attached to steel beams driven directly into the earth (as long as the surrounding soil is clear of large rocks and other debris).
If ground conditions around your facilities are not suited for beams, other anchoring methods can be used, including helical piles, ground screws and even concrete blocks. Your provider should be involved in testing the geology and soil of your site to help determine which mounting system is best.
While they may take more time to install, ground-mounted solar systems are generally sized to meet your energy needs based on the space you have available. When considering such a system, be sure to choose a location that won’t interfere with future construction plans. Also, bear in mind the cost of running lines between your commercial solar energy system and the grid. The further away your panels are from their point of interconnection, the more expensive your installation will be.
A solar solution that’s gaining speed: commercial solar carports
Solar carports are an increasingly popular type of commercial solar design—and can be a compelling choice for organizations looking for more than energy savings alone. Essentially, they’re steel canopies with solar panels mounted directly on top.
In addition to generating clean, renewable energy, commercial solar carports provide covered parking for employees, customers, students and faculty—offering plenty of shade on hot, sunny days and reliable protection from both rain and snow.
While the cost of building a commercial solar carport is typically more expensive than a roof- or ground-mounted system, in many cases it’s still the best option. That’s because carports offer organizations with limited roof or open space—or roofs that just can’t support roof-mounted systems—a way to maximize their energy-generating potential without compromising existing structures.
In addition, a growing number of organizations choose solar carports for the very visible statement they make. It could be that showing a clear commitment to environmental responsibility is as valuable to you as your energy savings, in which case solar carports offer a great way to make that statement.
While it’s true that constructing a solar carport may temporarily limit parking access or availability, the positives can easily outweigh the disruption. Many organizations take advantage of this opportunity to add integrated lighting and electric-vehicle charging stations to their solar carports—providing more convenience and added security.
As you can see, there are questions to be asked, conversations to be had and information to be gathered before you can confidently choose the right type of commercial solar design. As part of your solar planning process, be sure to talk to your solar provider about all the options available to you. Doing so will help you determine which commercial solar energy system will generate the most energy, as well as the most long-term value for your organization.
|Installation & Material Cost||Low to mid-range||Low to mid-range, and can vary depending on distance from interconnection point and required system foundations||Generally more expensive|
|Installation Timeframe||Usually the shortest||Medium to long, and can vary depending on system size, permitting requirements and the required system foundations||Medium|
|Disruption During Installation||Relatively low once the equipment and materials are on the roof||Relatively low||More disruptive if structure is built over a parking lot that will be in use during construction|
|Additional Features||Single and dual-tilt (to maximize sun exposure) options often available||"Tracker" systems (to maximize sun exposure) available for some ground-mounted installations||In addition to providing shade and rain/snow protection, integrated security lighting and vehicle charging stations can be added|
|Visibility||Generally not visible||Varies depending on system placement||Visible|
|Accessibility for Ongoing Operations & Maintenance||Easy, assuming good roof access||Generally easy||May require specialty equipment due to system height|