Design of Experiment (DOE) is a technique used to make effective and controlled experimentation and simulations, it helps in reducing the number of simulation runs. This will be very helpful in heterogeneous systems, since simulating such system is costing a lot of CPU resources and computations which leads to prohibitive simulation's time. Energy harvesting system is one of these heterogeneous (multi-physics) systems that contains components from different domains such as electrical both analogue and digital, mechanical, magnetic and thermal; simulating this this type of system will result in prohibitive cost unless utilising the power of DOE. In addition to that, DOE enables mathematical modeling to study the behavior of these systems and enable optimising performance of these complex systems efficiently.