Photovoltaic facade systems - a way to integrate green energy into the building structure

Interest in rooftop and ground-mounted solar power plants is huge and growing. It is not surprising that more and more applications for photovoltaics are being sought. One of these solutions is façade or wall-mounted photovoltaic power plants, which have been increasing in recent years. They are the ideal solution for buildings that do not have a suitable roof for a conventional rooftop installation, or as an addition to an existing rooftop PV system.

Facade systems are usually installed on a south-facing wall. They can be mounted parallel to the wall or with a slight tilt. However, due to this, they do not have as high a capacity as conventional installations and so it usually does not make sense to mount the modules on a wall other than the south-facing wall. Façade systems generally produce less energy than rooftop and ground-mounted installations. In general, wall-mounted solar panels produce more electricity in the winter months than in the summer. This is because the sun is lower in the sky during this time, so more direct sunlight hits the wall-mounted panels.

The naturally steep slope of wall-mounted solar panels requires special hardware for installation and securing. They are more difficult to fix than ground-mounted or roof-mounted solar panels, which are flat or have a gentle slope. The support system that holds the panels can be attached directly to the wall through anchors drilled into the wall, or the installation can use support columns that are erected against the wall and to which the panels are then attached. As façade systems fight gravity to remain upright, strong securing is essential to prevent displacement, damage and life-threatening accidents.

In terms of cleaning and maintenance, this system is easier than conventional ground and rooftop power plants. The accumulation of dirt, snow and other items is almost never a problem because rain washes away any debris and gravity prevents the accumulation of leaves and other debris, which contributes to easier cleaning. Wall-mounted modules are also more visible and do not require you to climb high and steep roofs to assess their condition. Climbing onto the roof is a burdensome and often risky task for many solar panel owners. Wall-mounted panels provide the advantage of easier visual access to keep track of cleaning or maintenance needs.

Building Integrated Photovoltaics (BIPV) is another, more demanding and more expensive option in terms of installation. It is a solar energy system that is seamlessly integrated into the building envelope and is usually part of building elements such as facades, roofs or windows. The BIPV system serves a dual purpose, being an integral part of the building envelope that not only converts solar energy into electricity, but also provides other necessary functions such as thermal insulation or noise protection. These systems can be installed during the construction of a new building or installed as part of the refurbishment of an existing building when one of the envelope components needs to be replaced.