Who we are



STS is the leader in PV modules quality control.


STS is a France-owned independent inspection and QA agency trusted by most of the leading PV developers and EPCs worldwide in the solar industry. We help our clients understand producers manufacturing capability, define quality plans, validate PV modules quality at production stage.

More than inspecting and testing products, STS helps PV system stakeholders guarantee the reliability and performance of PV modules procured for their projects. To ensure that non-conforming products can be replaced before being installed, we especially act during manufacturing stage. Results on the field have demonstrated our team’s ability to ensure product reliability and performance.


STS is today the largest quality assurance company in the PV modules sector, with more than 4% of the global PV modules manufacturing (2017) under 24/7 production monitoring by our 50+ full-time engineers.






STS has always been pushing forward quality standards in the photovoltaic industry. Manufacturing processes and global context have evolved over time, and STS constantly maintains its efforts to match trends in a fast-changing industry.


STS has released in May 2018 STS-STD-PVM1©, the one and only standard for manufacturing and dispatch of PV Modules.




Our European management team has more than 40 years cumulative experience in the photovoltaic industry; our quality mindset is the foundation of STS business model, leading the company to adopt a pragmatic approach based on best practices and the reality of the solar manufacturing to guarantee the quality and performance of PV modules manufactured at mass-scale.

Our auditors and engineers have cumulative experience of more than 250 years in manufacturing and quality fields in the photovoltaic industry; this gives STS the required assets to understand the risks and how to cope with the risks in PV modules manufacturing.