STH efficiency and catalyst concentration produces a multiplicative cost reduction. It can also be seen that the LCOH2 decreases more steeply for PC compared to PEC. PV+E has a much lower LCOH2 of around 3.6 $/kg(H2) for the base case. Increasing development distance, however, leads only to a roughly linear cost reduction (sublinear in logarithmic plot), indicative of weak interactions between selected parameters. In contrast to PEC and PC, parameter improvements (such as PV or electrolyzer CAPEX reductions) are largely independent of one another and do not produce multiplicative effects.