Abstract-Renewable energy production is important to solve problems related to security of supply, economic competitiveness, reduction of the economic energy burden to citizens and environmental impacts such as CO 2 emissions and pollution. Besides this the scenarios for the future foresee an increase in energy demand mainly due emerging economies and by this reason all the above mentioned issues will be crucial for EU Member States and many other countries around the world. Due to the inability of market to move to more sustainable energy systems, using a higher share of energy from renewable energy sources, it was necessary public action, creating RES support mechanisms in the majority of countries.Index Terms-Energy, RES, support mechanisms.
I. INTRODUCTIONRenewable energy is nowadays important worldwide since many human activities are increasingly related to energy consumption. Development of countries and economies are intrinsically related to energy and energy resources. To have energy resources does not imply a social and economic improvement of countries; nevertheless it is an important and necessary condition to strength and to maintain competitiveness of economies and to promote social improvements. European Union (EU) for example due to its high external energy dependency has changed its energy policy and renewable energy sources (RES) are seen as a key factor to overcome or at least to decrease this vulnerability [1]. Environmental aspects such as global warming are also forcing countries towards to more low carbon energy systems. International agreements and commitments such as the Kyoto protocol and pos-Kyoto agreements are also important drivers in this context.In EU the RES Directive 2009/28/EC has established targets to the share of RES in final energy consumption, namely 20% by 2020, and a minimum of 10% for renewable energy in the transport sector [2].Energy policies and pathways to achieve more sustainable energy systems are being planned in many countries of the world, in Europe, Asia, America, etc. Besides according to International Energy Agency (IEA) global energy demand will grow by 37% by 2040 in its central scenario and the distribution of energy demand will radically change with raising consumption in countries such as China, India and in the Middle East [3]. However even the developing countries, which are presenting a rapid consumption growth in all energy sectors, will have also to address energy security and M. Smitková is with the University in Bratislava, Slovakia (e-mail: miroslava.smitkova@stuba.sk).CO 2 emission reduction policies. For those countries RES is also an issue of great importance to their development.The perception of these problems lead to new energy policies and support schemes to finance RES since the market does not assure the necessary level of renewable without public action. This is mainly due to fossil fuel subsidies, weak internalization of external costs such as air pollution, energy security and the low flexible system design which causes market and reg...