It might seem odd to put solar panels on the side of walls in a region with mountains, but that’s exactly what’s happening in Switzerland. One of the cantons in the country is looking to be powered by at least 40% renewables by 2035 (which is quite achievable); with terrain being scarce it’s hard to place large solar installations. However, retaining walls in some areas get a lot of sunlight depending on their orientations (south facing would generate more for example) and with geography like Switzerland’s there are a lot of retaining walls. The cantons of Appenzell Ausserhoden’s first installation generations 325kW which is the equivalent of 52 Swiss households.
The PV system was anchored on and in the masonry using an adhesive technique. An anchoring depth of a maximum of 90 mm could not be exceeded so that the retaining wall would not be adversely affected.
Due to the close proximity to the asphalt, the solar panels’ components are subject to exceptional corrosion requirements and are anodized for protection. Indirect components are made of aluminum – only the screw anchors are made of stainless steel.