High capacity networks are needed for enormous quantity of internet traffic, which is driven by both the exponential growth of the number of people using the internet and the ongoing introduction of new high-bandwidth requiring applications. Combining optical and wireless technologies is a new and promising access network solution. The energy efficiency of telecommunication networks is therefore attracting increasing attention today than in the past. This study is aimed at evaluating energy efficiency of optical-wireless access network which combines Passive Optical Network (PON) and Long Term Evolution - Advanced (LTE-A) networks into one. The network was designed using Optimum Network Engineering Tool (OPNET) modeler software. Traffic was generated using inbuilt tools provided in the OPNET modeler software. Dynamic Bandwidth Allocation (DBA) algorithm was applied on the network and simulation was carried out using the simulation tool provided by OPNET to evaluate the effect of the DBA algorithm on the energy consumption and efficiency in the network. The findings showed energy utilization of 430 watt-second when DBA algorithm was applied on the access network as against 700 watt-second when it was not activated. This shows a 38.6% energy conservation. It was concluded that with the application of energy saving techniques to combined optical-wireless access network, substantial energy could be conserved even in the presence of heavy traffic without compromising the quality of service of the access network.