This dissertation seeks to raise awareness about harmful effects of fossil fuel and nuclear energy subsidies that have blocked transition from conventional energy to a decarbonized, renewable energy system. Today, humans face daunting challenges in the form of global warming, which results mainly from the burning of fossil fuels. To avoid catastrophe, the transition to a renewable energy regime should be an urgent priority; however, the reality is that the progress of renewable energy is very slow due to the various political and economic factors when compared to conventional energy resources. A chief factor is that the energy subsidy for fossil fuel and nuclear energy obstructs the "level playing field" for renewable energy. Energy subsidies for conventional energy can be understood in the context of the commodification paradigm, which regards nature as an object of conquest and supports the principle of more is better. Although fossil fuel energy damages the environment, economy, and social equity, all countries subsidize such energy, no matter the country's state of development. This holds true as much in the U.S. and the EU as in China, India and South Korea.

The oceans, which cover 71% of the earth, are threatened by the activities of conventional energy, which are underpinned by subsidies. These subsidies have contributed to the destruction of the marine ecosystem through increased GHG emissions like CO₂ and NO_x which cause a sea temperature increase and coral bleaching. Subsidies also significantly affect fishery overexploitation, oil pollution, and thermal pollution. In-depth empirical analysis of South Korea showed how fossil fuel and nuclear energy activities have threatened marine sustainability through thermal pollution, algae bloom (red tides), overexploitation, and oil-related marine pollution. Reforming subsidies of fossil fuel and nuclear energy should be a global priority because of imminent of global warming.

As strategies for energy subsidy reforms, first of all, humans need a new energy paradigm to replace the hitherto dominant commodification paradigm. On an international level, creation of an international renewable energy agency and creation of renewable funds will spur on energy subsidy reforms of all nations, especially developing countries. On a national level, government's role should change from growth-oriented economic policy to sustainable development that includes environmentally friendly energy systems. In terms of social welfare, energy subsidies should be transformed to direct income policy, which is more effective for the welfare of the poor. The South Korean government should exchange its current supply-oriented fishery policy, which relies heavily on energy subsidies, to a Marine Reserves policy and direct income policy.

For successful energy subsidy reforms, the government, NGOs, and private market should cooperate. Specifically, NGOs' role in monitoring and pushing government's energy subsidy reform is invaluable, considering the limits of modern bureaucracy and the profit-oriented market character. Most environmental problems, including global warming, have a close relation with fossil fuel and nuclear energy use. Historically, these energy systems have become entrenched deeply in society through energy subsidy policy. Energy subsidy reforms are a key to the environmental problem and accelerated transition to renewable energy.