[Front cover]

We propose and analyze an energy-aware traffic-adaptive routing strategy for large-scale mobile ad hoc networks (MANETs). Referred to as energy-aware geolocation-aided routing (EAGER), this protocol optimally blends proactive and reactive strategies for energy efficiency. Specifically, EAGER partitions the network into cells and performs intracell proactive routing and intercell reactive routing. The cell size and the transmission range are optimized analytically. By adjoining cells around hot spots and hot routes in the network, EAGER is capable of handling time-varying and spatially heterogeneous traffic conditions.