Mounting Systems

Solar PV mounting systems are available for just about any potential installation: sloped roof, flat roof, wall, ground or pole. Mounting systems hold the solar panels in place, protect them from wind damage and keep them cool by holding them above the mounting surface. Systems that allow 1- and 2-axis tracking can move to follow the sun’s position and boost output by 25% to 40% relative to fixed panels.

Types of Solar Mounting Systems

Ground mount systems

If you have sufficient area, you may want to install a solar system on the ground. These systems typically consist of a wedge-shaped structure made of steel support and anchored in concrete. A frame of aluminum or galvanized steel holds the panels in place.

Note: Ontario Power Authority is currently reviewing MicroFIT/FIT rates for ground-mounted solar systems, which are 64.2 cents per kilowatt vs. 80.2 cents for roof-mounted systems.

Tracking systems

Solar trackers orient PV panels toward the sun to increase energy output. Single-axis systems turn around a centre axis to let the panels move with the sun. Dual-axis systems turn around a centre axis and also tilt the panels to capture even more sunlight and increase output gains.
Learn more about PowerTrac Ground Mounted 1-Axis Solar Tracking Systems

Sloped roof mount systems

The typical mounting system for a sloped roof uses rails attached on top of the roof tiles to serve as a base for the solar panels. These rails may be attached to the tiles or rafters, depending on the roof pitch and type. Obviously if the attachment penetrates the framing, ensuring that the installation is watertight is critical. Telescoping the legs of the rails lets the panels be positioned at an optimal angle to the sun.

Flat roof mount systems

The most common mounting techniques for flat roofs include penetrated and ballasted techniques. As the name indicates, systems that penetrate the roof and attach to the framing must be installed with specialized sealing materials to avoid roof leakage. Ballasted mounting requires no framing and can withstand high winds. Ballasted systems rely on the weight of the solar panel array and racking system, plus additional material—usually concrete—to hold the array to the roof.

Considerations for roof mount systems

Life and age of the roof: Given the 20-year length of the MicroFIT/FIT contract, older roofs may need to be upgraded prior to a solar PV installation.

Structural considerations: Engineering and building permits are required to calculate wind/snow loads for most rooftop systems. This is why installers perform an engineering study before most jobs.

Performance: The direction the roof faces and its slope are also keys in overall solar PV system performance. In the northern hemisphere, south-facing roofs with a pitch of 30° to 45° are best, but systems can be designed around almost any roof. Roofs not oriented in the correct direction or pitched at the right angle can impact overall electricity production, but the loss in output still costs less than additional equipment required to achieve the optimal angle.

Pole mount systems

When ground and roof space is limited, you can still mount a solar panel on a pole. These are often dramatic, high-visibility installations and have the added advantage of allowing the panels to be oriented and pitched to capture as much sunlight as possible. You can add a tracking system to further improve output. The poles are generally sturdy steel pipe cemented in the ground.

Wall mount systems

Another option when ground and roof space is limited is the wall mount system. If you mount panels flat on your wall, your performance will be better in winter than summer, due to the lower angle of the sun and reflection off the snow. You can improve performance year-round by increasing the angle with a frame to hold the panels. Wall mounts also offer the advantage of much easier installation and maintenance than roof mounts.