Electric buses (e-buses) are essential to sustainable public transport, but their real-world efficiency and range are heavily affected by auxiliary systems, particularly the Heating, Ventilation, and Air Conditioning (HVAC) system. This study investigates how ambient temperature variations and HVAC loads influence energy consumption, range, and efficiency in e-buses operating under diverse climatic conditions.
The methodology combines field data collection from urban e-buses across seasons—including extreme summer and winter—with controlled lab testing. Field measurements included ambient temperature, HVAC demand, vehicle speed, state of charge (SOC) variation, and energy consumption. These inputs were used to develop real-world duty cycles, replicating actual thermal loads, passenger profiles, idling periods, and driving patterns.
In the lab, these cycles were simulated using a chassis dynamometer and environmental chamber, with HVAC systems tested at controlled ambient temperatures (-5°C to 45°C). **Energy split analysis** quantified the proportion of energy used for propulsion versus HVAC, revealing the **range impact** under extreme conditions.
Key results show a 20–40% range reduction during peak HVAC operation, with variability tied to cabin insulation, HVAC control strategies, and route dynamics. The study compares climate control, thermal pre-conditioning and dynamic thermal management, to optimize efficiency.
By bridging real-world data with lab validation, this research delivers actionable insights for OEMs, fleet operators, and policymakers to mitigate HVAC-related energy losses and ensure reliable e-bus deployment across climates