tThe recent developments in green energy technologies and the importance of using clean energies havemade the renewable resources more attractive for distribution network operators, specifically due to theirinexhaustible and non-polluting features. In this way, the present study initiates an integrated dynamicdistribution network expansion planning (DDNEP) in which most of the planning alternatives alongwith renewable and non-renewable distributed generation (DG) are taken into account. The proposedframework considers the important cost terms, including both the investment and operational ones.The uncertainties regarding the intermittent nature of renewable DGs, load demand, and energy pricehave been well-regarded in calculating the cost components. With the aim of a precise calculation ofoperation and interruption costs, the load duration curve (LDC) has been established for modeling of thenetwork loads. Moreover, both the possibility of operating the DG units in islanding mode, and, the loadtransferring through the reserve feeders have been interrogated in the problem in order to improve thenetwork reliability. In the present research, to provide an accurate evaluation of reliability indices, and tocover all of the uncertainty states, the required conditions for the successful and safe operation of islandhave been suitably studied in the problem. In numerical evaluations, a combination of improved geneticalgorithm (IGA) and optimal power flow (OPF) is employed to solve the integrated problem in the 54-bustest system. The obtained results are discussed in details.