Energy Management is of primary importance in mobile devices due to increasing functionality coupled with rapid battery drain. Our analysis reveals that users differ in their context and resource usage patterns which can be profiled towards developing predictive models for energy savings. A key challenge lies in providing user-adaptive security in an energy-aware manner due to increasing sensitivity of user data and analyzing the energy-security trade-offs which we address in this work. Towards this goal, we develop a statistical user model to predict available energy at a given time instant using historical user data and further describe a generic multi-level security model for mobile devices. The available energy from the user model in conjunction with the energy estimates from the security model can be used for energy-aware security adaptation in mobile devices.