Wide scale penetration of renewable electricity in the Greek energy system in view of the European decarbonization targets for 2050

The key policy analyzed in this paper, is the achievement of a significant decarbonization of the Greek Energy System by the year 2050 through the decarbonization of the two sectors presently responsible for the highest levels of greenhouse gas emissions (GHG) emissions, namely power and transport. The objective is to reduce GHG emissions by 2050, through the maximization of renewable energy sources (RES) penetration in electricity, with a simultaneous intensive electrification of the transport sector and the electrical interconnection of non-connected islands. An important parameter considered in the present work is that expansion planning of power systems under environmental constraints leads to a rather complex techno-economic analysis involving large scale penetration of Renewable Energy Sources. The penetration level of variable renewable electricity is subject to a number of restrictions implied by the need for (a) storage capacity to decrease the energy curtailment which can occur when the customer load is low and RES electricity generation is high (b) fast reserve capacity to deal with variations of variable RES or combined heat and power (CHP) electricity generation (c) transmission system expansion related to the penetration of areas with high RES potential. New methodologies are developed and a number of novel scenarios are formulated in conformity with the European energy strategy towards 2050.