In recent years, environmental pollution caused by excessive exploitation and utilization of the Earth’s fossil fuels, extreme exploitation of land resources, and excessive emissions of carbon dioxide (CO₂) has caused people to think about how to reduce CO₂ emissions and capture the existing CO₂ in the atmosphere. The reduction of CO₂ emissions can be summarized into two aspects. Firstly, people could use renewable energy to provide energy support for economic and social development. These renewable energies mainly include solar energy; wind energy, hydro, and marine energies; geothermal energy; and biomass energy. The second aspect is the sequestration and conversion of CO₂. CO₂ is also a form of carbon resource that can be a favorable alternative to traditional carbon resources. The utilization of CO₂ can solve both environmental pollution and depletion of traditional carbon resources at the same time. In this paper, the development of five renewable energy sources and their applications in China were discussed, and the methods of effective sequestration and conversion of CO₂ were presented. Energy and environment are closely related to the development of modern society. The problems caused by excessive CO₂ emissions cannot be ignored and the sequestration of the greenhouse effect requires joint efforts of mankind.