Quantifying the lifetime of photovoltaic modules is getting increasingly important with the aim to drive further technological developments, to reduce financial risks and to accelerate the deployment for new photovoltaic applications. Many lifetime limiting factors can be directly or indirect related to temperature and strain acting on the laminate constituents. In this work a novel optical sensing solution is proposed based on Fibre Bragg Grating sensors which enables a direct validation of the thermo-mechanical strain within a PV laminate. A combined sensor package enables a direct monitoring or validation of the thermo-mechanical stress of a PV cell during production, accelerated testing and field testing. Initial testing shows a high potential due to the non-invasive nature, high sensitivity, scalability and optical transparency.