Modern life is convincing us that renewable energy technologies, policies, strategies should be disseminated all over the world to provide sustainable development. As an instrument, feed-in tariffs of renewable energy should be designed considering public finance opportunities, buying power of consumers in order to tackle administrative barriers as an optimization strategy. The authors used the comparison, data analysis and logical access methods. The paper provides evidence from leading countries in the industry, explores ongoing challenges in the application of feed-in tariff policies, analyses the optimal methodologies to give recommendations to stakeholders.