Abstract. Many regions, not only in the Europe, introduce plans for the modernization of energy systems so that in a few or several years most of the demand for electricity was being able to cover using renewable energy sources. The aim of this paper is to present the possibility of estimation of appropriate power supply based on the renewable energy sources in the context of the whole energy system in the annual balance, taking into account the technical and the economic optimization strategies. The article presents also the simplified structure of the 100% renewable energy system supported by energy storage systems and the production of synthetic fuels.

ABSTRACT. The main goal of this paper is to present various aspects of electricity market monitoring and to focus on the monitoring of economic parameters, placing a special emphasis on market power, market performance and behavioral monitoring. This paper provides a view of the monitoring and its components. It presents available monitoring techniques and further it indicates the need to modify the existing structure or to develop a new structure of the monitoring system based on new indices which could be used by both operator and market participants.

ABSTRACT. The main goal of this paper is to present new indices and a new structure of the electricity market monitoring system. The proposed structure, along with the analytical methods and indices applied to this structure, could be used from the viewpoint of both market operator and market participants. This paper also describes, in a rather simplified manner, the algorithms of market monitoring on the case study of Spanish electricity market.JEL Classification: Q4, E03, E37, O10, N70