The energy required for continuous glass melting usually accounts for about 30~75% of the total energy consumptions supplied to the glass industry, and the energy cost contributes to about 10~25% of total glass manufacturing cost depending upon the type of glass and manufacturing efficiency. Typically, energy efficiency of glass furnaces offers major opportunities for manufacturing cost reduction.Significant rising of energy cost, environmental requirements for clean air and pressure for reducing global warming and carbon dioxide emissions, as well as the cost of capitals are main drivers for the technology developments. In this paper, energy efficiency of glass furnaces is discussed. Technology developments in selective batching, oxy-fuel firing with preheating batch and cullet, non-conventional advanced melting systems, such as segmented glass melting and submerged combustion melting, as well as using math modeling to optimize fuel distribution for energy savings are presented.