Types of Installations

For a residential system, most solar panels will be mounted on the roof of your home. The panels need to face the sun, thus they will be pointed south if you live in the northern hemisphere. Or north if you live “down under”. You also need to point the panels UP at the sun. As a general guideline, you till the panels up, at the same angle as your LATITUDE.

If you have the space, another option is to mount the panels on the ground. They can be static mounted (don’t move) or you can mount the panels on trackers. The trackers and be single axis (east-west) or dual axis (est-west and up-down). A dual axis tracker can increase your power output by 30% or more. Thus, though they may cost a little more to install, they usually more than pay for themselves.

Ground Mount

In cases where there is not sufficient roof space, solar modules can also be mounted on the grounds of your property. The most common type of ground mount is a wedge structure constructed from steel supports anchored in concrete footings. The remainder of the structure is built from aluminum or galvanized steel.

 

Pitched–Roof Mount

Roof mounts are more difficult to install and maintain, particularly if the roof orientation and angle are not compatible with the optimum solar array tilt angle. Penetrating the roof seal is inevitable and leaks may occur. Also, it is important to achieve a firm and secure attachment of the array mounting brackets to the roof. Attaching the mounting brackets to the rafters will provide the best foundation, but this may be difficult because module size and rafter spacing are usually not compatible. If there is access to the underside of the roof, 2 x 6-inch blocks can be inserted between the rafters and the attachment made to the blocks. Attaching the array to the plywood sheathing of the roof may result in roof damage, particularly if high winds are likely.

Flush Mount This first mounting type is for a roof which faces close to due south. This can be done on any slope (at least 18.4 pitch) of roof but performs best on a steeply pitched roof. Angle Mount This type of mounting is typically done on a roof with a lower pitch where the owners do not mind having the panels stick up and away from the roof. This type of mount will result in more efficiency for the PV system. This is also used for ground mounts. Fin Mount This mounting system is for homes with shallow roof pitches where the roofs slope to the east and to the west. It is the most obtrusive of the mounting styles but is sometimes the only option available. These systems will be fairly efficient, but will need more roof area than the others.

Flat–Roof Mount

There are few mounting techniques you can choose from when racking a PV array on a flat roof: Attached, Ballasted and Hybrid technique which uses both ballast and structural attachments. Installing a system on a flat roof does not require a reroof, it is naturally ventilated and it can be aligned for optimum orientation and tilt. At the same time, mounting a system on a flat roof requires very carefully designing due to extra weight on building from the frame and additional materials like pavers when using ballasted mounting technique. Also, it must be designed carefully so PV panels do not shade one another. With any ballasted system it maybe necessary to have the strength of the roof checked by a structural engineer.

Attached This type of installation require penetration and connection to the framing. Ballasted Ballasted mounting of systems for flat roofs require no penetration and can withstand winds up to 90 mph. Ballasts mounts rely solely on the weight of the array, racking system and additional material, like concrete paver, to hold the array to the roof. Hybrid Hybrid installation is a combination of ballasted and structural attachments. A minimally attached, or hybrid, system takes advantage of both attached and ballasted features. A hybrid racking system will require minimum number of penetrations and some level of ballasting. The concept for the hybrid system is rather simple: the fewer penetration used, the more ballasting required and vice-versa.