In this paper we propose a query-driven approach for tuning the time/energy trade-off in sensor networks with mobile sensors. The tuning factors include re-positioning of mobile sensors and changing their transmission ranges. We propose an algebraic query optimization framework that explores these factors while utilizing collision-free concurrent data transmissions with different degrees of data filtering and aggregation. Categories and Subject Descriptors C.2.1 [Computer – Communication Networks]: Network Architecture and Design – Wireless communications; H.2.4 [Database Management]: Systems – Distributed databases, Query processing General Terms Algorithms, Design, Performance, Experimentation Keywords Mobile Sensors, Sensor Networks, Query Optimization, Data Transmission Algebra, Collision Domains