# Sustainable Operation of Active Distribution Networks
## 4 Case Study  
The suggested approach was applied to a case study comprising the IEEE 33-bus radial distribution network with 1000 residential building prosumers, 32 clusters of PEVs, one wind park, and three photovoltaic parks integrated to it. The developed models were verified through detailed simulation results. Four types of residential buildings and PEVs with different technical specifications were considered in this work. Probability density functions (PDFs) were used to obtain the arrival and dwell periods of the PEVs and can be found in [16]. Figure 7a shows the total number of connected PEVs to the distribution network, while Figure 7b shows the number of connected PEVs to each node of the network. In order to take into consideration the stochastic behavior of the ambient temperature, various trajectories were generated and used. Figure 8a displays the base trajectory of the dataset selected for demonstration purposes together with its variation area. Similarly, various trajectories of the actual electricity price were randomly generated and the respective data are shown in Figure 8b. Various trajectories of the total ADN load consumption as well as of the total power generated by the wind park and the photovoltaics were randomly generated and the respective data are shown in Figure 9a,b, respectively. Figure 7: (a) Total connected PEVs in the ADN. (b) Connected PEVs to each node of the ADN. In addition to the proposed optimization approach, a typical ADN operation case study was considered, in which the residential building thermal loads as well as the hosted electric vehicles were not subject to any optimization. In this case, the objective of the operation of the HVAC system is to maintain the internal temperature of buildings at a predetermined set point. Electric vehicles only absorb power in order to charge their batteries and attain the desired energy level and they do not have a V2G operation ability. The examination of this case study was taken into account in order to compare its results with the respective results of the proposed strategy for the optimization of the operation of the ADN. The total HVAC electrical power consumption and electrical power consumption of the other building loads of all residential buildings hosted in the examined active distribution network are given in Figure 10a. As can be observed, the residential buildings absorbed the largest amount of thermal power around 15:00 p.m., when the electricity price was very low, as the proposed algorithm aims to reduce the total operation cost of the examined system. Moreover, in this time period, the ambient temperature is high enough, and obviously the cooling requirements of the residences are increased. Figure 10b provides the comparison of the total buildings' HVAC power consumption between the proposed optimization examined case study and the typical scenario of the ADN's operation. It was observed that when the suggested optimization algorithm was implemented, a significant reduction in the HVAC systems' required power was achieved. Figure 11 depicts the HVAC system's power consumption of the clusters of the buildings connected to the distribution network  
Figure 8: (**a**) Outdoor temperature. (**b**) Forecasted price of electricity. Figure 9: (**a**) ADN load consumption. (**b**) WT and PV power production and their variation areas. nodes as a result of the optimal dispatch of the respective total HVAC system's power consumption. These vary due to the fact that each node comprises a different number of residential buildings with different technical specifications. Figure 12a,b presents the indoor temperatures of all buildings hosted by the ADN obtained by the proposed ADN optimal operation scheduling technique and the execution of the typical ADN operation, respectively. All temperatures were maintained within the considered permissible comfort range of 21-26 \({}^{\circ}\)C. Figure 13 depicts the power consumed by the non-flexible electrical loads of two indicative residential buildings hosted in the examined ADN.