Solar components are often built with specific tasks in mind. Helical piles and ground screws are driven into the earth to secure racking, and roof mounts are attached to structural supports and flashed to prevent leaking. Since panels are placed on a variety of surfaces, not every mounting technology will work in every application — installers won’t likely use rail-free mounts to put panels on a hillside.
But manufacturers and solar contractors are finding success in changing up the status quo with non-traditional applications for racking, mounting and tracking technologies. SunModo has found yet another feature for its ground-mount and rooftop racking, an installer learned that roof ballasts and racking can also work on the ground and Mechatron Solar used its newest dual-axis tracking system as a carport.
Roof ballasts on ground mounts
Nickels Energy Solutions of Upstate New York has experience in both ground-mount and rooftop installations. Primarily working in the residential market with some commercial experience, the solar contractor has had its hands on a lot of mounting technology.
When it encountered a residential project where ground penetration was difficult due to rocky soil and the system needed to be as low-key as possible, Nickels Energy found that roof ballasts work just fine on the ground if the site is prepared properly.
“I think that this is one of those solutions that can work in the right application, and it’s important that installers be solution-minded, because when you’ve got a property owner that is interested in making this change, we’ve got to be able to be open so we can find the way to get that done and make it happen,” said Kevin Nickels, VP of sales for Nickels Energy Solutions.
Ballasts are weighted, non-penetrative mounts for solar systems. Large pre-made or poured blocks of concrete are typically used in ground-mount systems to hold solar racking in place, and smaller concrete pavers are used on roof-ballast arrays. Racking for roof ballasts is lower-profile and built for higher wind loads from rooftops.
With those qualities in mind, Nickels Energy Solutions found a workaround for its client. When solar enters new communities, a common criticism is that panels aren’t visually appealing, and residents don’t want to see acres of solar panels in their neighbors’ yards or in their community.
To make roof ballasts and racking work, Nickels prepared a flattened square footprint in the customer’s yard, removed vegetation, layered it with a bed of rocks and installed a barrier on the square’s edge. Since it’s not mounted to the ground, the array can be easily moved or removed if needed.
The low-profile system is at a disadvantage for production during winter months, because snow piles on the panels, but with New York’s net-metering program, customers have generated enough excess solar credits to power through the snowy season.
“An installer who hasn’t been there before I think would want to look at a solution like this as a card you have in your back pocket,” Nickels said. “While looking into soil reports or doing their own testing, if they find that this ground mount is going to be a real bear to get through, this is a way to avoid some concerns.”
Roof, multi-pole, ground and canopy racking
SunModo’s established racking system, SunBeam, was devised to work in both ground- and roof-mount applications. It works mounted with a ground ballast as well as it would when secured to a roofing membrane. But after years on the market, SunModo engineers decided to improve on the racking’s design.
“It was time for us to do a redesign, to rethink the product and what we wanted to do,” said Roland Jasmin, director of engineering at SunModo. “Instead of going out looking at our competition and being better than what they had to offer, we said, ‘Let’s be better than the SunBeam. We’re going to beat our own product.’”
The company released SunTurf, which, in addition to its standard roof, ground and canopy uses, added a multi-pole configuration. Multi-pole means the system is supported by a single row of posts instead of the usual two rows, reducing the number of penetrations needed to mount the system in the ground.
SunTurf can still use a two-post configuration, and in both settings can hold panels in one-portrait or two-landscape. On flat rooftops, the system keeps its post height, making it possible to be installed over roof obstructions. SunTurf was independently wind-tested to ensure it wouldn’t budge with its added height.
“We’ve had customers, especially in cities like New York, where they have high-rises. They have a lot of flat surfaces on top of buildings, but nothing around for a traditional ground mount,” Jasmin said. “They don’t have the acreage that they can put solar on, so they want to be able to add solar to the rooftop, but they also want to enjoy the rooftop.”
Engineers reduced pipe cutting by offering posts in 60- and 120-in. lengths, which are compatible with SunModo’s proprietary ground screws and augers. SunTurf has drill-free assembly, and its vertical posts are fastened using three screws.
“For me, I’m constantly challenging my team to be better, to do better, because if we don’t improve on our products, our competitors will,” Jasmin said. “Let’s think about this —where else can this be applied? How much of the engineering can we leverage? Because we are a small team, we don’t have a bunch of design engineers just sitting around waiting for something to do, so when we do something, it is very deliberate.”
A dual-axis carport
Solar carports are designed to accommodate clearance for vehicles, providing shade for those cars parked underneath. They’re overwhelmingly fixed-tilt solutions, but Mechatron deployed its latest dual-axis tracker, the M18kD-20 — which is the tallest solar tracker model in the United States — in a six-unit carport system at an office parking lot in Burlingame, California.
The 200-kWDC tracking solar carport system installed by Elios Solar is powering an electric vehicle charger and providing 90% of the power needed at Kahala Tower, an office building near San Francisco International Airport.
The 16-ft-tall systems still track throughout the day without bringing panels below 9.5 ft off the ground, leaving plenty of headspace for vehicles, while still providing shade. Mechatron modified the array’s tracking angles, keeping them from moving below a 20° zenith.
“The challenge (of this project) was more with the city, because they requested a lot of structural integrity mechanisms, ballast-based design and wind-proof adequacy,” said Michael Fakukakis, CEO of Mechatron Solar.
The tracking carports were built to withstand a magnitude 8 earthquake. The M18kD-20, like all other Mechatron trackers, is gearless, and has built-in fail-safes for adverse conditions like high winds.
Mechatron’s trackers are supported by single posts with cement pillars. Altogether, the six trackers can cover 22 parked vehicles, and give enough clearance for emergency vehicles to access the parking lot’s fire lane. Fakukakis said he hopes to expand the concept of dual-axis trackers as carports across the country.
Whether it’s racking, tracking or ballasts, solar installers are finding new applications for established technologies to put solar in places it might not have been otherwise.