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Photovoltaic mounting systems are used to fix solar panels on surfaces like roofs, empty plots etc. These mounting systems enable retrofitting of solar panels on existing roofs or easily incorporated as part of the building envelope at construction stage.

Mounting on roofs

PV panels mounted on roof

The PV array may be mounted above and parallel to the roof surface with a gap of several inches for cooling purposes. In case of flat roofs, a separate structure with a more optimal tilt angle is mounted on the roof. Proper roof mounting can be laborious. Particular attention is be paid to the roof structure and the weather sealing of roof penetrations. It is typical to have one support bracket for every 100 Watts of PV modules. For new construction, support brackets are usually mounted after the roof decking is applied and before the roofing materials is installed. The crew in charge of laying out the array mounting system normally installs the brackets. The roofing contractor can then flash around the brackets as they install the roof. Masonry roofs are often structurally designed near the limit of their weight-bearing capacity. In this case, the roof structure must either be enhanced to handle the additional weight of the PV system or the masonry roof transitioned to composition shingles in the area where the PV array is to be mounted. By transitioning to a lighter roofing product, there is no need to reinforce the roof structure since the combined weight of composite shingles and PV array is usually less than the displaced masonry product.

Mounting as a shade structure

An alternative to roof mounting is to mount the system as a shade structure. A shade structure may be a patio cover where the PV array becomes the shade. These shade systems can support small to large PV systems. The construction cost with a PV system is a little different than for a standard patio cover, especially if the PV array is part of the entire shade roof. If the PV array is mounted at a steeper angle than a typical shade structure, additional structural enhancements may be necessary to handle the additional wind loads. The weight of the PV array is 3 to 5 pounds/ft², which is well within structural limits of most shade support structures. Other issues that are considered include:

• Simplified array access for maintenance.
• Module wiring, if visible from underneath, may be carefully concealed to keep the installation aesthetically pleasing.
• Cannot grow vines, or must be diligent about keeping it trimmed back from modules and wiring.

Building-integrated photovoltaics

Main article: Building-integrated photovoltaics

The CIS Tower in Manchester, England was clad in PV panels at a cost of £5.5 million. It started feeding electricity to the National Grid in November 2005

Building-integrated photovoltaics (BIPV) are photovoltaic materials that are used to replace conventional building materials in parts of the building envelope such as the roof, skylights, or facades. They are increasingly being incorporated into the construction of new buildings as a principal or ancillary source of electrical power, although existing buildings may be retrofitted with BIPV modules as well. The advantage of integrated photovoltaics over more common non-integrated systems is that the initial cost can be offset by reducing the amount spent on building materials and labor that would normally be used to construct the part of the building that the BIPV modules replace.

Roof-Jack mounting system

In the mid-1980s Ascension Technology's principals, then working at the Massachusetts Institute of Technology, developed the Roof-Jack mounting system for attaching PV arrays to pitched and shingled residential roofs. The motivation of that effort was to simplify and reduce the cost of residential PV array balance-of-systems.

See also

• Solar tracker
• MPPT
• Rooftop photovoltaic power station
• Stand-alone photovoltaic power system
• Grid-connected photovoltaic power system