In order to satisfy the needs of electricity use, but also to safeguard the reliability of the existing National Electricity Distribution Network, HEDNO must build new electricity distribution infrastructures as well as modernise existing electricity distribution infrastructures. In this context, HEDNO opted for the construction of a new K/D 150/20 kV in the Municipality of Chania, which will be called K/D Chania II and will be built within the Naval Station of Crete. The new K/D Chania II will be powered by the Y.T. side via double cable line 150 kV from the existing H/S of Chania. The main feasibility and destination of the new K/D Chania II, is to ensure the adequacy and increase the reliability of electrification of all kinds of consumers (domestic, commercial, industrial etc.) of the area of Akrotiri, the eastern part of the city of Chania, the airport, the Polytechnic, the commercial port and finally the Shipyard of Souda. In the present phase the city of Chania is powered by a single PO and the network of the area shows saturation points and unable to serve with the required degree of reliability even the existing demand, especially during the summer months, where the peak of the year now appears due to the extensive use of air conditioners and the increase of tourist traffic in the prefecture of Chania.With the installation of the new K/D Chania II, within the geographical area of the serviced loads will achieve significant reduction of the long lines. In this way, the following are achieved: the electricity losses are significantly reduced proportionally the probability of error or failure along the lines improves the quality of power provided to consumers reduces the frequency and the duration of power interruptions increases the stabilisation of voltage.These factors have become particularly important in recent years, due to the demanding and sensitive power quality devices that are now used extensively both in homes and in enterprises (electronic and digital computers).