This article presents the analysis on the law of energy consumption and economic development, the features of renewable energies, the current technical availability and the effectiveness of CO₂ emission reduction. The author believes that the total energy consumption is experiencing a stage of continuous growth in China, and the renewable energies will not play a major part in the energy mix in the coming forty years. The fossil energy will continue to play a major role in China. To use the fossil energy efficiently shall become a top priority in the course of CO₂ emission reduction and low-carbon economy development. The article reviews the achievements and existing problems of the fossil energy use and development in China, and provides the countermeasures to efficiently use the fossil energy as follows: firstly, to have a reasonable GDP growth rate and establish the supervision index system of the total consumption of fossil energy; secondly, to establish the assessment and evaluation method on the energy efficiency of the fossil energy use on a life-cycle basis and the CO₂ emission, to improve the fossil energy use efficiency through continuously optimizing the methods; thirdly, to explore and create a modern low-carbon life and consumption mode in line with Chinese context in view of the status quo of the fossil energy resources in China; fourthly, to encourage and coerce energy saving by fully leveraging the fiscal and tax policy and the administrative measures; fifthly, to enhance the research & development, and the roll-out application of the technology, material and products with which the fossil energy can be used efficiently; sixthly, to enhance the capital input in order to realize the optimized and efficient use of the fossil energy.