Implementing renewable energy is an essential first step in achieving sustainability goals, energy security, and economic development. Renewable energy policy supports the goals of sustainability, energy security, energy access, and green economic growth. Development of renewable energy sources is required in order to achieve sustainable national energy systems. Capital investment in renewable energy sources has been promoted by the use of such policies as feed-in tariffs, renewable portfolio standards, and green financing. Numerous data from different countries indicate that effective policies give rise to positive feedback loops supporting both environmental sustainability and economic development which modifies the trade-off mentality. Environmentally friendly public policy promotes circular economy principles and result in a considerable reduction of greenhouse gas emissions. Energy security is strengthened by the diversification of energy sources and the decrease of dependence on fossil fuels. This gives consumers of energy substantial control over their costs and makes them less susceptible to the instability of market conditions affecting the supply of energy. Energy access will be improved the most. This is particularly true of the rural poor countries. Renewable energy systems that are decentralized and supported by appropriate policies have provided electric energy for users that formerly did not have it. The high level of investment, the lack of financial resources, the lack of institutional abilities, and the ambiguity of public policies prevent the effective implementation of renewable energy policies especially in the developing countries. Renewable energy policies and sustainable development combine synergistically to provide greater sustainability through economic growth in countries which have effective regimes. This combination shows that renewable energy policies can provide for a conversion to sustainable development practices. These policies are integrally related to improved integration of financial institutions, regulatory frameworks and international cooperation. Effective hybrid metrics and incentives that do not favor particular technologies may provide further improved sustainability, energy security, and economic development.