Countries around the world meet their electrical energy demand by utilizing fossil fuel based, nuclear or renewable energy sources. In contrary to fossil fuel based and nuclear energy sources which have negative environmental impacts and which increase energy import dependency, renewable energy sources (RES) minimize the negative environmental impacts and decrease energy import dependency which places a big burden on the economies. Energy generation from RES is disadvantageous in comparison to conventional energy sources because of its high investment costs and as it is a new technological area. Countries apply different incentive systems with the purpose of eliminating such disadvantages and encouraging the use of RES for electricity. Turkey is highly dependent on external energy sources, has substantial amount of RES potentials and has an incentive system to promote energy generation from these sources. In Turkey and around the world, there are various barriers to RES deployment. Knowing these barriers and taking convenient measures is necessary for the development and deployment of RES. In this study, 18 investors having investments in the area of RES in Turkey were interviewed and the results of RES incentive system and other additional supports in application were assessed through a survey study. As a result of the analysis of the survey data, effectiveness of RES incentive system and other additional supports was assessed and its pros and cons in application were determined. (C) 2014 Elsevier Ltd. All rights reserved.