The end of the use of internal combustion engines is scheduled for 2035 in the US and 2040 in France. These evolutions will require Electric Vehicles (EVs) to evolve significantly. In this context, the use of PV modules is one of the alternatives considered to make vehicles partially energy self-sufficient and limit the size of the batteries. However, this integration should not be at the expense of the mechanical behaviour of the car parts. An optimization of this integration is therefore necessary. To optimize the mechanical behaviour of the structure in regard with standards, the development of a numerical model is proposed. This model of a one-cell panel is validated through experimental tests, and further used to optimize the stack using a Design Of Experiment (DOE) method. The optimized sample including solar cells is 2.7 times lighter than an equivalent automotive part made of steel.