Lightweight PV for Structurally Constrained Roofs

The Zehnder Group — internationally leading in solutions for healthy indoor climates — wanted to expand the existing PV system at its Gränichen production site. The challenge: the majority of the roof surface has no load-bearing substructure and is heavily constrained in terms of structural capacity — a typical situation in industrial and storage buildings.

Ampere Dynamic designed a solution together with AEW Energie AG as grid operator using around 12,000 frameless lightweight modules. At only 5.6 kg/m², the modules could be installed without roof penetration using a special adhesive method — where conventional systems fail due to structural constraints. A partial area was equipped with standard modules, while the majority required the lightweight solution.

With a total output of around 450 kWp, Zehnder now generates a significant share of its electricity needs directly on site. Surpluses can be stored in storage systems in the future. The system not only reduces energy costs, but also directly cuts Scope 1 and Scope 2 emissions — a direct contribution to the company’s ESG goals.