Automotive air conditioning systems improve passenger comfort and safety while keeping pace with changing environmental and technological requirements. This review evaluates the historical development, technological progress, and future trends of automotive air conditioning systems, primarily focusing on passenger vehicles, where cabin comfort and individualized thermal control are essential. The analysis examines the transition from early, energy-intensive cooling systems typically operating at a coefficient of performance (COP) of around 1.5 to modern, environmentally friendly alternatives that achieve COP values of approximately 3.0 or higher, highlighting the impact of regulatory measures such as the Kigali Amendment. A particular focus is placed on comparing refrigerants, especially the transition from HFC-134a to HFO-1234yf, with a discussion of their ecological impact and compliance with regulations. Innovative technologies, including adsorption cooling, AI-enhanced climate control, and the integration of renewable energy, are being explored as potential solutions to current challenges. Initially, 121 articles were reviewed, with 84 chosen for detailed examination based on their relevance, methodological soundness, and contributions to the field. The results reveal the trade-offs among efficiency, cost, and sustainability, highlighting the need for ongoing innovation to balance energy usage and environmental stewardship. Future studies should focus on creating refrigerants with extremely low global warming potential, improving battery efficiency in electric vehicles, and utilizing AI for tailored climate control. By tackling these issues, the automotive sector can offer more sustainable and efficient air conditioning options that align with consumer expectations and environmental regulations.

Waste heat recovery from automotive exhaust gases represents an important strategy for improving vehicle energy efficiency. This study experimentally investigates the performance of a thermoelectric generator (TEG) system based on TEC1-12706 modules running under different cold-side cooling conditions and incorporating a Hot Rolled Steel (HRS) protective layer on the hot side. The HRS plate was used to ensure uniform heat distribution and protect the thermoelectric module against thermal shocks generated by a 250 °C heat source. Four cooling regimes were experimentally analyzed: natural convection and forced airflows equivalent to 40, 60, and 90 km/h. The results proved that increasing airflow intensity significantly improved the temperature difference across the module, from approximately 16 ± 2 °C under natural convection to nearly 40 ± 2 °C at the highest airflow velocity. Correspondingly, the steady-state voltage generated increased from approximately 0.25 ± 0.01 V to over 0.60 ± 0.01 V under an 82 Ω resistive load. The measured hot-side temperature remained below 75 °C in all experimental conditions, confirming the thermal protection capability of the HRS layer. The experimental data also revealed a near-linear relationship between voltage and temperature difference, consistent with the Seebeck effect. The proposed configuration shows the feasibility of combining thermal protection and forced convection cooling to improve the stability and electrical performance of thermoelectric waste heat recovery systems intended for low-power automotive auxiliary applications.

This paper investigates the potential of localized air-curtain microclimate control to reduce HVAC energy consumption in electric vehicles while maintaining occupant thermal comfort. The study compares conventional full-cabin cooling with driver-focused and passenger-focused air-curtain configurations under controlled ambient conditions of 32 °C. The experimental framework combines analytical airflow and heat-transfer modeling with comparative HVAC performance evaluation using power consumption, time to reach thermal comfort, and Predicted Mean Vote (PMV) analysis. The results show that the air-curtain configurations reduce HVAC power consumption from 3.2 kW for conventional cooling to 2.3 kW and 2.5 kW for the driver- and passenger-focused configurations, corresponding to energy savings of approximately 22–28%. In addition, localized airflow significantly accelerates thermal comfort attainment, reducing stabilization time from 8 min to 4–5 min while maintaining PMV values within acceptable comfort limits. The findings demonstrate that occupant-centered air-curtain microclimate strategies can improve HVAC energy efficiency, reduce auxiliary energy demand, and support more sustainable and range-efficient operation of next-generation electric vehicles.

The increasing need for sustainable mobility and enhanced energy efficiency in internal combustion engine (ICE) vehicles has intensified interest in waste heat recovery technologies, particularly thermoelectric generators (TEGs). However, low conversion efficiency and sensitivity to high exhaust gas temperatures from internal combustion engines still limit their practical application. This study investigates the thermal and electrical behavior of a commercial TEC1-12706 SR module subjected to controlled temperature conditions that simulate exhaust system environments. Using copper and aluminum protective plates to manage heat distribution, experiments were conducted at input temperatures of 250°C and 350°C to assess temperature evolution, thermal gradients, voltage, current, and output power. Copper’s high thermal conductivity facilitated efficient heat transfer on the hot side, while aluminum increased distribution of thermal dissipation on the cold side, though progressive heating reduced ΔT over time. The findings underline the critical role of thermal shielding and cooling strategies in preserving module integrity and maximizing conversion efficiency. This research provides experimental insights and design considerations for integrating TEGs into automotive waste heat recovery systems.