Planning for a 100% independent energy system based on smart energy storage for integration of renewables and CO2 emissions reduction

EU import dependence on hydrocarbons and resulting negative environmental impact related to their use led to setting of new measures and energy policy that will make, in time, a post carbon society more feasible and achievable. Energy systems of this society will be based on four pillars: Renewable Energy, Buildings as Positive Power Plants, Energy Storage and Smart grids in combination with Plug-in Vehicles. All these pillars must be supported by the use of smart energy storage. The results of previous research has shown that in order to increase security, efficiency and viability, there is need for energy storage, in primary or secondary form, in order to transfer energy surplus from period of excess to the period when there is a lack. The problem of today’s storage systems is that they increase the cost of already expensive, distributed and renewable energy sources. That makes the large scale use of storage systems even less economically viable in market circumstances, despite economics of scale. The paper shows results of an energy planning methodology applied to several cases where use of smart energy storage system helps integration of energy flows, transformations and energy demand at the location of the energy end-use or close to it. Main results presented in this paper focus on planning a 100% independent energy system of Croatia. They also show the role of energy storage in a self-sustainable energy system with excess electricity production from renewable energy sources. The technical and financial analyses have been carried out for periods of one year taking into consideration demands and renewable energy production during all hours.