Manufacturers, buyers, project developers and banks: many players are involved in the construction of ground-mounted photovoltaic systems. At a crucial point in such large-scale projects, everyone benefits from the VDE SPEC “Solar Module Quality Standard”, which was published in fall 2024.
The three-part document is intended to simplify and therefore speed up purchasing processes, explains Gerhard Kleiss from the engineering firm 8p2, who initiated the VDE SPEC together with his partner. “Most people who buy solar modules on a large scale will quickly reach agreement on delivery conditions and payment with the manufacturer. A typically more contentious point is the quality of the modules and how this is verified.” Component quality is absolutely crucial. “With a specified service life of around 25 to 30 years, solar modules are the most expensive part of a PV system. The feasibility and financing of the entire project depend on their durability.” This results in time-consuming discussions when closing a sale – even though buyers always pose the same questions and requirements. “The VDE SPEC seeks to change that. It contains a checklist that serves as a basis for sales talks.
According to Kleiss, the feedback a few months after publication has been consistently positive. “Manufacturers are happy when customers place orders using the VDE SPEC because it saves a lot of time.” This despite the fact that they were not involved in the SPEC’s creation. The SPEC was supported by a consortium of purchasing companies, including solar installation developers and a bank. Project manager Kleiss emphasizes the advantages of a VDE SPEC, such as the short development time and flexibility. “After we did the preliminary work and delivered a draft text, it took six weeks from the application to the publication of the VDE SPEC.”
This is an enormous time saving compared to the lengthy coordination and translation processes for traditional standards, which can sometimes take years. And, if new technologies come onto the market that require additional tests, the VDE SPEC can easily be updated. Even though they do not entail any obligations, Kleiss says that such documents help to create more uniformity on the market. “Experience shows that manufacturers use them as a guide.”
The SPEC is written in English and is therefore internationally oriented. It is free to download and use.