Evaluating the Impact of Network Investment Deferral on Distributed Generation Expansion

Abstract

Distributed generation (DG) can offer an alternative planning approach to utilities to satisfy demand growth and distribution network security, planning and management issues. However, an appropriate framework is required to foster the integration of DG within grid network planning, thus avoiding potential inefficiencies in electricity supply infrastructure. In this work, in order to capture the effects of network investment deferral on DG expansion, different regulations for distribution network operators (DNOs) ownership of DG and how they influence the optimal connection of new generation within existing networks are examined. Using a multiyear multiperiod optimal power flow, DNOs preference for the siting and sizing of DG installation are analyzed

Efficient immune‐GA method for DNOs in sizing and placement of distributed generation units

“…One of the appropriate models reported in the literature is calculating the difference between total loss of the system before and after DG placement [1], [5], [14], [16], [18].…”

“…In some models [16], the DNO should pay/receive equal to the electricity price multiplied by amount of loss reduction/increase and in some models [1], [5], [14], [18] a fix incentive, i.e. ψ, is paid to DNO for each MWh reduction of active losses .…”

“…One method for exact calculation of this deferral is integrated planning models [12] in which network reinforcement and DG planning are performed simultaneously. The other methods use simplifying assumptions by assuming that each MVA of installed DG reduces the need for reinforcing substation and feeders [1], [18]. In this model, the incentive due to investment deferral in network is proportional to the total installed DG in the network, as follows:…”

“…The DG units change the flow over the feeders of the distribution network by injecting active and reactive power to their interconnection node. They may cause different benefits for Distribution Network Operators (DNOs) as reported in the literature, such as: network investment deferral [1], [2], active loss reduction [3]- [6], environmental emission reduction [7] and reliability improvement [8]. These benefits are obtained just if they are connected in the appropriate sizes and locations.…”

“…This assumption is made to make the problem more realistic since DG units are commercially available in certain sizes but this will make the solution getting far from the optimum value. Few literature deal with unbundled DNO [1], [6], [14], [18], [19]. The reference [6], proposes a method based on Kalman Filter algorithm to find the optimal size of DG units to reduce active losses the location of these units are found by clustering the buses in networks into the number of DG units and selecting the largest bus in each cluster as the best candidate bus for DG installation.…”