Route diversity improves the security of Wireless Sensor Networks (WSNs) against adversaries attempting to obtain sensitive sensor data By limiting the fraction of data relayed over each link and/or routed through each relay node, route diversity can be achieved, thus, extracting useful information from the network is rendered more challenging for adversaries. Sensor nodes operate with limited energy resources, therefore, energy consumption of security mechanisms is a central concern for WSNs. In this paper we evaluate the energy cost of route diversity for security in WSNs through a novel Linear Programming framework. We characterize energy dissipation and data relaying behaviors of three route diversity techniques to mitigate node capture only, eavesdropping only, and node capture and eavesdropping attacks. Effects of node density, network area, level of resilience, and network topology on energy cost are investigated. (C) 2014 Elsevier B.V. All rights reserved.