In wireless mobile adhoc networks (MANETs) channel and energy capacities are scarce resources, a lot of energy-efficient routing protocols for MANETs have been previously proposed to take into consideration the nodes? residual energies when establishing routes between source-destination pairs.

In this paper we are not trying to introduce a new routing algorithm to be added to the already proposed stack of energy-efficient protocols, but rather, we identify a problem in cost-based energy-efficient routing for MANETs, we call this problem "Flooding Waves". We show that the "Flooding Waves" is a serious problem in dense networks, to the extent that the excessive energy overhead consumed in these waves can outweigh the gain achieved by energy-efficient path selection. We propose the "Delayed-Forwarding" as a solution for this problem. We provide both a simulation analysis and a simple theoretical framework to validate and support this solution.