Display omitted •The impact of ambient temperature was analyzed using the chassis dynamometer and real-world driving.•It shows good performance at an ambient temperature approximately (20 to 30) ℃.•Ambient temperature affects energy recovery, with battery consumption increasing by 35.4 % when compared to −15 ℃ as opposed to 24 ℃.•Real-world driving shows higher efficiency than certified range. Electric vehicles are affected by ambient temperature, which is closely related to the driving range. This study conducted a comprehensive evaluation of the energy efficiency using both a chassis dynamometer and actual driving environments. Under various temperature conditions, the motor energy, battery energy, regenerative energy, and energy efficiency were analyzed using a Combination US06 mode of the chassis dynamometer and the Konkuk University route to realize real-world driving scenario. The results revealed that low temperatures increased the motor and battery energy consumptions (compared to 24 ℃ ambient temperature, −15 ℃ required 35.4 % more.) while hindering regenerative energy recovery during driving. This study confirmed that the optimal energy efficiency for electric vehicles is attained at approximately (20 to 30) ℃. Notably, the energy efficiencies were real- higher than the certified values under real-world driving conditions. Moreover, when the HVAC system is turned on, it increases battery energy consumption by 5.4 % in the summer and by 12.0 % in the winter, influencing the overall energy efficiency with higher battery energy consumption during its operation in both seasons. Therefore, the study findings highlight the importance of considering the ambient temperature and HVAC system usage when evaluating vehicle energy efficiency and driving range. Furthermore, this study emphasizes the need for future vehicle designs and energy management systems to optimize the performance under various ambient conditions, thereby enhancing the overall energy efficiency and extending the driving range.