Connected dominating set (CDS) has been used widely in mobile ad hoc networks by numerous routing, broadcast, and time synchronization protocols. Although computing minimum CDS is known to be NP-hard, many distributed protocols have been proposed to construct a small CDS. However, these protocols are either too complicated, need non-local information, are not adaptive to topology changes, or fail to consider the difference in energy consumption for nodes within and outside the CDS. In this paper, we present two Timer-based Energy-aware Connected Dominating Set Protocols. Our protocols extend the Mac-layer Timer-based Connected Dominating Set protocol (MTCDS) so that the energy level at each node is taken into account when constructing the CDS. Simulation results have shown that our protocols effectively construct an energy-aware CDS with a very competitive size and prolong the network operation under different levels of nodal mobility.