The synthesis of new efficient low cost solar cells made with earth abundant materials requires on the one hand the development of such materials and, on the other hand, an adequate design of the solar cell that optimizes their use. This latter part is all the more challenging as the materials can be tuned in a variety of ways, adjusting for instance their doping, composition, bandgap and thickness. The high number of parameters that can be adjusted implies that finding their optimal combination is a task in itself, which is presently addressed by a parametic optimisation: optimising one parameter at a time with respect to the cell efficiency, the others being kept constant. Despite its apparent simplicity, this method is time consuming and is not proven mathematically to allow to find the optimal parameter set. Mathematically proven methods can now be easily used in the field of photovoltaics, which allow a simultaneous optimisation of an increased number of parameters, implying a susbtantial decrease in the computation time, along with an increase in the precision of the prediction. A review of present methods and how we have improved them for speed, correctness and precision will be provided.