The challenges of global warming and energy depletion are increasingly severe and good. Exacerbated by traditional energy sources and industrial processes. Cars consume a lot of conventional energy, and designing more efficient energy recovery systems can not only extend the driving range of vehicles but also reduce wasted energy. Enhancing energy recovery in the automotive industry to improve fuel efficiency has become a major focus of global automotive research. This paper proposes to achieve this through the implementation of thermoelectric generators, regenerative braking, Rankine cycle, electric turbochargers, and mechanical flywheels technology. Detailed examination of the energy recovery efficiency and environmental benefits of each technology. Performing basic numerical computations using simulation software and testing the changes in various parameters under different standard conditions. In particular, the report highlights how mechanical flywheels may drastically lower pollutants and fuel consumption. As a result, mechanical flywheel systems are recommended to be installed in electric vehicles (EVs) and future research should concentrate on improving their performance and integration. The evaluation of these technologies is based on two primary criteria: overall efficiency and environmental friendliness, this paper will propose some methods to improve energy efficiency and reduce energy waste.