The mounting system for solar panels is critical and often overlooked. There are numerous types of solar mounts that can be installed on a property owner’s land or buildings, each designed for a specific set of conditions. Whatever the roof or land arrangement, there is a solar mounting solution for it.
For traditional pitched roofs with composite shingles, the classic roof rack features rails that sit a few inches above the roof’s surface. This space allows water and debris to pass below the solar modules as well as air-flow, which keeps the modules cooler, which provides greater electricity production efficiency. The rails sit atop attachments, which are usually screwed into the building’s rafters or purlins, flashed and sealed to guarantee waterproofing. Structural engineers determine the number of roof attachments required.
Brackets and Clamps
Standing seam metal roofs use clamps to mount the solar panels to the roof. They can be clamped easily into place on the roof’s protruding metal seams and attach to the panels securely. There are solar specific attachments designed for the many different styles and shapes of metal seams.
Property owners sometime express concern about the impact of mounting solar panels on the integrity of their roofs. Solar installers are experts at matching the mounting system to the roof and maintaining the reliability of the structure. The solar industry’s reputation depends upon ensuring that roofs are not damaged in the process of installing solar panels, and indeed, it has a nearly flawless track record.
Non-penetrating, Ballasted Solutions
For flat roofs, which are often waterproof membranes (TPO or PVC), solar installation often involves a solar mounting system that is held in place by its weight and therefore does not require roof penetrations. For high-wind areas, like those in hurricane zones, weight alone may be insufficient, so a heat-adhering attachment is added, in which a waterproof plate is heat-sealed to the membrane.
Flat roofs are most often seen on industrial buildings, and older structures may need additional structural buildout to support the weight of the panels. This can reduce the cost-effectiveness of the solar system. A professional solar company can help you determine the cost-benefit profile of a solar system on your roof.
Solar systems can also be installed on the ground where there is space for them. Large solar arrays are usually ground-based. In these cases, the mounting system is significantly different than roof-based systems and offer greater flexibility, and often, efficiency.
Standard Ground Mounts
Typically, a round mounting system is anchored to the soil by driving supports below the surface. In rocky soil, ground screws or helical piles – giant screws with pointed ends – are screwed into the rock to anchor the mounts. The height of the structure ranges, from just two feet above the ground on the bottom edge to seven or more feet tall at the top. The solar company will usually plant pollinator grasses beneath and around the panels to keep the soil active and productive.
Ground mounting systems have the advantage of dynamic mounting systems. That is, panels can be placed at a fixed orientation – usually facing south at a slight tilt – or can track the sun in a number of ways to increase solar exposure and thereby boost energy efficiency. That is called a fixed tilt.
Panels can be mounted on a system that follows the sun throughout the day, swiveling across an east-west axis to significantly increase electricity production. These systems maximize sun exposure, usually for utility-scale commercial installations. These systems do require more maintenance because they include mechanical systems that move the panels, and they require more acreage because the space between rows is wider, in order to avoid the panels’ shading one another. These tracking systems also quickly sheds snow from the face of the modules in the winter.
A growing niche in solar mounts involves attaching them to floating docks on lakes and large retention ponds. This allows arrays to produce electricity without consuming resources on the ground. They have the added benefit of reducing evaporation and algae growth while the water cools the panels and enhances their efficiency. These systems can be more expensive to install, but the permitting tends to be simpler.
Solar Shade Canopy
Elevated structures above parking lots, atop parking garages, and covering other paved areas provide both shade and electricity production without added land use. These structures are ideal for campuses and business centers, where available land and roof space is limited. Businesses often compound the value of these systems by using the electricity produced for electric vehicle charging stations below.