Effect of encapsulants on the thermomechanical residual stress in the back-contact silicon solar cells of photovoltaic modules – A constrained local curvature model

•The effect of the encapsulants on the IBC silicon cell stresses in a PV module were studied using finite element analysis.•The encapsulant modulus and thickness affect the cell stress significantly and the effect of CTE of the encapsulant is negligible.•A constrained cell curvature model is proposed to explain the effect of the encapsulant.•The cell stress is directly proportional to encapsulant modulus and inversely proportional to encapsulant thickness.•The increased cell stresses due to thinning of the silicon cells can be negated by adopting to a softer and thicker encapsulant.