Unique alternatives to rooftop solar for small-scale installations
Roofs aren’t the only place to harvest a few kilowatts of solar energy for smaller energy applications. Homes with yards or in off-grid locations can use the ground underfoot or south-facing walls to mount some solar panels. Solar panel manufacturers offer a number of alternatives for homeowners looking for a different type of installation.
Pole-mounted photovoltaic systems are often found in roadside and smaller off-grid applications, powering devices such as traffic lights and water pumps. But those are side-of-pole mounts and produce significantly less energy than a typical array. However, top-of-pole mounts (TPM) can hold many more modules and work well for off-grid solar projects.
With one pole as a foundation, TPM systems adapt well to undulating topographies. Successive placement under these conditions allows the posts to remain level with respect to each other.
“One of the biggest advantages is that you can simply place it where it needs to be placed,” said Steve Schumacher, National Sales Manager, Preformed Line Products (PLP). “It’s just a lot easier than trying to run a racking system on a slope.”
PLP carries TPM systems in horizontal and vertical module orientations and a multi-pole model with multiple footrests. These TPM systems can contain up to 15 modules and a maximum of about 5 kW for each table with high production panels.
In addition, TPMs are adjustable with one post, both in orientation and angle. On the models of PLP, panels can be moved from 15 ° to 65 ° in steps of 10 °. This can be done by means of a mounting sleeve that is attached to the top of the post with an adjustable support rod. Schumacher said people often reorient their TPM systems in the fall and spring to compensate for the sun’s changing path throughout the year.
“You could physically go out and turn it on the pole,” he said. “They try to get as much power as possible from their solar panels.”
Wiring TPMs can be done by drilling a hole at the top of the post, running the cabling to the bottom, and running through another hole on the side of the post. PLP uses concrete foundations that vary in length and diameter depending on the soil type. They have been tested to withstand snow loads of approximately 90 psf and wind loads of 150 mph.
“There are limitations, but they are quite extreme,” said Schumacher.
Carports, awnings and ground fixings
Rooftop solar is the predominant choice for residential solar, but Mike Zuritis, president of Solar Foundations USA, said he finds more people are choosing ground-mounted projects when we consider what it takes to build a Overhead mount array. Penetrations are usually needed for rooftop arrays, so any roof maintenance means taking the modules into account.
“Placing it on a ground mount allows you to orient the array to optimize PV production, and the maintenance options are clearly simplified when it is on the ground itself,” he said. “You potentially have a lot more versatility in terms of what you can use that structure for.”
Solar Foundations USA focuses on producing ground mounted structures for residential and small commercial customers.
Solar Foundations’ structures use ground screws instead of I-beams. On larger projects, some developers will use piles that require pull-out tests to determine the capacity of the foundation in the bottom of a construction site, but Solar Foundations has found that ground screws work in precarious soil conditions and do not require frequent pull-out tests, skipping that step altogether and saved. money.
The company’s fixed ground brackets, canopies, carports and pavilions are custom designed on a project-by-project basis with industry-leading heights of up to 9 ft and use a rectangular steel sub-structure for all systems. Like TPMs, the system orientation is not tied to the direction of the roof. Solar Foundations has manufactured fixed tilt systems with a front height of up to 5 ft for use on farms and around livestock. Expansion is a simpler prospect for fixed-tip systems where no roof space is an issue. As long as there is more garden, there can be more modules.
Staying on trend with non-traditional solar structures, Smartflower has a different approach to generating renewable energy. Where customers can ask installers to hide modules on roofs or in construction sites as much as possible, the Smartflower product of the same name is intended to draw attention to itself.
In its fifth iteration, the 2.5 kW PV “sculpture” is also a solar tracker with petal-shaped modules attached to a column. At sunrise the modules of the Smartflowers unfold, follow them throughout the day and close at sunset. Mark Conroy, president of Smartflower Solar, said the system is designed to mimic the heliotropic properties of a sunflower.
“Just as people buy Teslas or Ferraris to basically show off a new art form, that’s the same idea as Smartflower,” he said.
It qualifies for the same tax credits and rebates as traditional ground and roof solar panels. All components are packed together and the main structure comes pre-assembled. Conroy said trained contractors can install the Smartflower in about a day. The utility foundation and trench can be dug with a skid steer loader, and the Smartflower itself can be placed with a forklift or crane.
The system can use cast and prefabricated foundations as a foundation, as well as spiral piles or a steel base. If the Smartflower has a steel base, it can be moved more easily for temporary off-grid applications.
Wall mounted awnings
If the roof or garden is not an option, installers can look to the walls of south-facing buildings to mount a solar panel. Racks are available to mount modules vertically and tilt from a wall surface to create an awning.
Some installers have modified existing mounting hardware to mount modules to walls, but solar structure manufacturer Opsun carries Sunrail WM, a wall mounting system that works on all common wall types. Modules can be placed flat against the wall or at any angle, and in landscape or portrait orientations.
As with the Smartflower, solar panels for vertical or wall mounting can be an aesthetic choice, reducing production due to visibility. However, if you place them at an angle, more energy will be produced than if they are flat against the wall.
When a customer is considering smaller solar panels, the roof does not have to be the standard. With a large enough yard or unfettered walls, there is potential for solar energy in almost any setting.