With the rapid popularization of new energy vehicles, the energy efficiency level of smart charging piles directly affects the stability of the power grid and operating costs. This paper constructs an energy efficiency analysis framework, conducts in-depth research on the structure of the electrical system and the energy transmission mechanism, accurately identifies key loss links, and quantitatively analyzes the impact of charging loads on the power grid. The test results show that the 10kV direct power supply mode can increase energy efficiency by 2.3%. Peak-valley electricity price regulation can reduce electricity costs by 28%. Distribution topology optimization reduces line losses by 18%. Energy-saving measures for communication systems can reduce communication module energy consumption by 48%. The comprehensive optimization plan ultimately achieved an energy-saving rate of 28.4%, providing theoretical basis and technical support for the construction of charging infrastructure. It is of great significance for promoting the sustainable development of the new energy vehicle industry and the realization of the "dual carbon" goals.