Developing energy-aware applications is a well known approach to software-based energy optimization. This promising approach is however faced with a significant hurdle when deployed to the environments shared among multiple applications, where the energy consumption effected by one application may erroneously be observed by another application. We introduce EFLECT, a novel software framework for disentangling the energy consumption of co-running applications. Our key idea, called energy virtualization, enables each energy-aware application to be only aware of the energy consumption effected by its execution. EFLECT is unique in its lightweight design: it is a purely application-level solution that requires no modification to the underlying hardware or system software. Experiments show EFLECT incurs low overhead with high precision. Furthermore, it can seamlessly port existing application-level energy frameworks — one for energy-adaptive approximation and the other for energy profiling — to shared environments while retaining their intended effectiveness.