In this paper, numerical and experimental investigations of broadband random vibrational energy harvesting using monostable and bistable piezoelectric cantilevers are presented along with relative performance comparisons. Simulations and experiments reveal that a linear-monostable energy harvester can outperform its bistable counterpart for very low and relatively high random excitation levels. The bistable configuration generates more power only for a limited excitation intensity range slightly above the threshold of interwell oscillations. Under broadband stochastic excitation, a bistable energy harvester can potentially be preferred only if it is designed to operate at a known excitation intensity, otherwise using a monostable harvester is more robust and practical.
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