Today, more and more emphasis placed on the energy usage and the electricity supply. Rising energy prices and the effect of greenhouse gases in the past few decades caused subjective improvement and optimization of energy efficiency in the industry. In this regard, many technologies such as distributed generation, energy storage and distribution lead times for energy optimization are presented. We live in a high-technology society and for improving these technologies, electricity share of global energy resources are expected to grow. With a smart production, distribution and energy consumption in the future, we hope to continue the electrical energy posterity. This paper reviews concepts and researches done on optimizing the energy efficiency.